Heterocyclic modulators of cannabinoid receptors

ABSTRACT

Heterocyclic compounds which modulate cannabinoid receptors are presented. Pharmaceutical compositions containing these compounds, methods of using these compounds as modulators of cannabinoid receptors and processes for synthesizing these compounds are also described herein.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Pat. App. Ser. No. 60/949,536filed Jul. 13, 2007 and to U.S. Pat. App. Ser. No. 61/036,321 filed Mar.13, 2008. These applications are incorporated by reference herein ittheir entirety.

FIELD OF THE INVENTION

The present invention is directed to new heterocyclic compounds andcompositions and their application as pharmaceuticals for the treatmentof disease. Methods of modulating cannabinoid receptor activity in humanor animal subject are provided for the treatment of diseases.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

None.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

None.

REFERENCE TO SEQUENCE LISTING

None.

BACKGROUND OF THE INVENTION

CB1 and CB2 are two cannabinoid receptors that belong to the GPCR familyand have very different functions and distribution. While no x-raystructure is available for these receptors, various models have beendescribed on the basis of the x-ray structure of rhodopsin, a GPCRbelonging protein responsible of the light sensitivity in vision.Matsuda L A, Lolait S J, Brownstein M J, Young A C, Bonner T I,Structure of a Cannabinoid Receptor and Functional Expression of theCloned cDNA, Nature 1990, 346:561-4. CB1 is abundantly expressed in thecentral nervous system and is most dense in the basal ganglia,cerebellum, hippocampus, and cortex and in the peripheral nervoussystem, it is expressed in such sites as the testis, eye, urinarybladder, and adipocytes. CB2 is mainly expressed in the immune tissues,in cells such as those in the thymus, marrow, spleen, pancreas, and inglioma and skin tumor cells. It was recently demonstrated that CB2receptors and their gene transcripts are widely distributed in thebrain. A third cannabinoid receptor seems to be present as some chemicalanalogues exhibit cannabinoid biological activity without activating CB1and CB2. Di Marzo V, Bifulco M, De Petrocellis L, The EndocannabinoidSystem and Its Therapeutic Exploitation, Nat Rev Drug Discov 2004,3:771-84.

BRIEF SUMMARY OF THE INVENTION

Novel heterocyclic compounds and pharmaceutical compositions thatmodulate CB1 and CB2 have been found, together with methods ofsynthesizing and using the compounds including methods for the treatmentof cannabinoid receptor-mediated diseases in a patient by administeringthe compounds.

A class of heterocyclic compounds, useful in treating cannobinoidreceptor mediated disorders and conditions, is presented and defined bythe structural Formula I:

or a salt, ester or prodrug thereof, wherein:

-   -   R¹ is selected from the group consisting of NH₂, NHR⁴, NR⁴R⁵,        any carbon atom of which may be optionally substituted;    -   R² is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted;    -   R³ is selected from the group consisting of hydrogen, halogen,        alkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, any        carbon atom of which may be optionally substituted; and    -   R⁴ and R⁵ vary independently and are selected from the group        consisting of aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted,        and by the structural Formula III:

or a salt, ester or prodrug thereof, wherein:

-   -   R¹ is selected from the group consisting of NH₂, NHR⁵, NR⁵R⁶,        any carbon atom of which may be optionally substituted;    -   R² is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted;    -   R³ and R⁴ are independently selected from the group consisting        of hydrogen, halogen, alkyl, cycloalkyl, heterocycloalkyl, aryl,        and heteroaryl;    -   R⁵ and R⁶ are independently selected from the group consisting        of aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl; and    -   when R² is hydrogen, R³ is not t-butyl, bromo, methoxy, or

Heterocyclic compounds presented herein possess useful cannabinoidreceptor modulating activity, and may be used in the treatment orprophylaxis of a disease or condition in which a cannabinoid receptorplays an active role. Thus, in broad aspect, pharmaceutical compositionsare provided comprising one or more the compounds together with apharmaceutically acceptable carrier, as well as methods of making andusing the compounds and compositions.

Methods for modulating cannabinoid receptors with heterocyclic compoundsare also provided. Methods for treating a cannabinoid receptor-mediateddisorder such as neuropathic pain or addiction in a patient in need ofsuch treatment comprising administering to said patient atherapeutically effective amount of a heterocyclic compound orcomposition presented herein. The use of compounds disclosed herein canbe used in the manufacture of a medicament for the treatment of adisease or condition ameliorated by the modulation of cannabinoidreceptors.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary as well as the following detailed description ofthe preferred embodiment of the invention will be better understood whenread in conjunction with the appended drawings. It should be understood,however, that the invention is not limited to the precise arrangementsand instrumentalities shown herein.

For a more complete understanding of the present invention, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIGS. 1A and 1B show functional activity data of the compound of Example2.

FIGS. 2A and 2B show functional activity data of the compound of Example3.

FIGS. 3A and 3B show functional activity data of the compound of Example5.

FIG. 4 shows paw withdrawal threshold versus time for IP administeredcompound of Example 3.

FIG. 5 shows paw withdrawal threshold versus time for IT administeredcompound of Example 3.

FIG. 6 shows reversal of allodynia as a function time with IPadministered compound of Example 3 and IP administered morphine.

FIG. 7 shows the synthetic steps of making the compound of Example 3 asused in in vitro and in vivo biological studies.

FIGS. 8A and 8B show the characterization of CP55,940 (FIG. 8A) and thecompound of Example 3 (FIG. 8B) in recombinant human CB1 and CB2GTPγ[³⁵S] assay systems. Levels of receptor activation are calculatedand are expressed as a percentage relative to the response of 1 μMCP55,940.

FIG. 9 shows the effects of different doses of the compound of Example 3(i.p.) on thermally evoked hind paw withdrawal latency in naïve rats(n=10 per group). (A) The time course of percent maximal possible effect(% MPE) and (B) the area under the curve (AUC) of 1.0, 3.0, and 10 mg/kgof the compound of Example 3 and the vehicle. #P<0.01 as compared to thevehicle. *P<0.001 as compared to 1.0 or 3.0 mg/kg of the compound ofExample 3 and to the vehicle. ⁺P<0.05 as compared to 1.0 mg/kg of thecompound of Example 3 and the vehicle. Each point represents themean±s.e. mean.

FIG. 10A depicts the development of tactile allodynia after spinal nerveligation. FIG. 10B depicts development of tactile allodynia after i.p.administration of paclitaxel for 4 days. Each point represents themean±s.e. mean.

FIGS. 11A, 11B and 11C show the effects of compound of Example 3 (i.p)on tactile allodynia in a spinal nerve ligation neuropathic pain modelin contralateral normal, ipsilateral injured rats (n=6 per group).Compound of Example 3 increases in the withdrawal threshold of thenerve-injured paw in a dose-dependent manner. FIG. 11A shows the timecourse of 5.0, 10, and 15 mg/kg of the compound of Example 3. FIG. 11Bshows the area under the curve (AUC). FIG. 11C shows the dose responsecurve of the anti-allodynic effects the compound of Example 3 at 30 minin a spinal nerve ligation neuropathic pain model (ED₅₀=7.48 (CI5.6-9.9) mg/kg, i.p.). Pretreatment with 5 mg/kg i.p. of a selective CB2antagonist AM630 antagonized the effects of the compound of Example 3.Data are expressed as mean±s.e. mean. *P<0.001 versus all other groups.⁺P<0.05 versus 10 mg/kg and 15 mg/kg of the compound of Example 3.

FIG. 12 shows the effects of CB1 and CB2 selective antagonists on theantiallodynic effects of 10 mg/kg of the compound of Example 3i.p. in aspinal nerve ligation neuropathic pain model in rats (n=6 per group).I.p. administration of 5 mg/kg of AM251, a CB1 antagonist or a 5 mg/kgof AM630, a selective CB2 antagonist alone had no effect. Administrationof 5 mg/kg AM600 i.p. 15 min prior to the administration of 10 mg/kg ofthe compound of Example 3i.p. reversed the antiallodynic effects of thecompound of Example 3 (AM630+ the compound of Example 3 group).Pretreatment with 5 mg/kg AM251 i.p. followed 15 min later by 10 mg/kgof the compound of Example 3i.p. did not affect the antiallodyniceffects of the compound of Example 3 (AM251+ the compound of Example 3group). *P<0.001 as compared to vehicle, AM251, AM630, and AM630+ thecompound of Example 3 groups. ⁺P<0.001 as compared to vehicle and AM251groups.

FIG. 13 shows the effects of the opioid antagonist naloxone on thecompound of Example 3 and AM1241-induced antiallodynic effects in aspinal nerve ligation neuropathic pain model in rats (n=6 per group).The compound of Example 3 (10 mg/kg i.p.) significantly attenuatedtactile allodynia threshold that that of a CB2-selective agonist AM1241(15 mg/kg i.p.). Administration of the opioid antagonist naloxone (10mg/kg i.p.) per se did not affect paw withdrawal threshold. Pretreatmentwith 10 mg/kg naloxone i.p. followed 15 min later by 10 mg/kg of thecompound of Example 3i.p. did not affect the antiallodynic effects ofthe compound of Example 3 (Noloxone+ the compound of Example 3).Reversal of the antiallodynic effects of 15 mg/kg of AM251 i.p. bypretreatment with 10 mg/kg naloxone i.p. *P<0.001 as compared to vehicleand AM1241. ⁺P<0.001 as compared to vehicle, naloxone, andnaloxone+AM1241 groups. ^(#)P<0.01 as compared to vehicle andnaloxone+AM1241 groups.

FIGS. 14A, 14B, 14C and 14D show the effects of the compound of Example3 (i.p) on thermal hyperalgesia and tactile allodynia in apaclitaxel-induced neuropathic pain model in rats (n=8 per group). FIG.14A shows the compound of Example 3 suppressed paclitaxel-evoked thermalhyperalgesia in a dose-dependent manner. In the AM630+ the compound ofExample 3 group, pretreatment with 5 mg/kg AM630 i.p. followed 15 minlater by 15 mg/kg of the compound of Example 3i.p. reversed theanti-hyperalgesic effects of the compound of Example 3 (P<0.001). Theeffect of 5 mg/kg AM1241 i.p. on reversing thermal hyperalgesia wassignificantly less than (P<0.05) that noted for 15 mg/kg the compound ofExample 3i.p. FIG. 14B shows the calculated ED_(so) of the compound ofExample 3 for suppressing thermal hyperalgesia at 20 min was 13.5 mg/kgi.p. (95% CI=8.2-22 mg/kg). FIG. 14C shows the compound of Example 3dose-dependently attenuated tactile allodynia in this model. FIG. 14Dshows an increase in the % MPE withdrawal threshold AUC with an ED₅₀ of24 mg/kg i.p. *P<0.05 or less as compared to 5 mg/kg, 10 mg/kg, and 15mg/kg the compound of Example 3 groups. ⁺P<0.05 or less as compared 15mg/kg the compound of Example 3 group. **P<0.05 or less as compared to10 mg/kg, and 15 mg/kg the compound of Example 3 groups.

FIG. 15 shows after the administration of the compound of Example 3 withthe start of paclitaxel administration for 14 days [four daysconcomitant with the administration of paclitaxel and continued forfurther 10 days] resulted in prevention of paclitaxel-induced neuropathyin 100% of rats. Administration of paclitaxel alone of 4 days resultedin development of neuropathy in 100 percent of rats. The compound ofExample 3 for four days only resulted in short-lived prevention ofpaclitaxel-induced neuropathy. Melatonin did not provide any protectionagainst neuropathy in this model.

FIGS. 16A, 16B, 16C and 16D show the absence of psychoactive cannabinoideffect of the compound of Example 3. Exploratory behavior was tested inthe open field following i.p. administration of vehicle, the compound ofExample 3, WIN 55, 212-2, and haloperidol (n=6 per group). The followingparameters were scored for 60 minutes: distance traveled (FIG. 16A),ambulatory time (FIG. 16B), vertical activity (FIG. 16C), and number ofzone entries (FIG. 16D). ⁺P<0.05 versus vehicle and the compound ofExample 3. *P<0.05 versus the compound of Example 3.

FIG. 17 shows the effects of the compound of Example 3 onPaclitaxel-induced neuropathy in rats (right paw). Peripheralneurophathy started to develop within a few days of paclitaxeladministration, but was prevented by administration of the compound ofExample 3.

FIG. 18 illustrates paclitaxel-induced peripheral neuropathy in rats.The peripheral neuropathy started to develop within a few days ofpaclitaxel administration and reached a plateau by the 10th day.

FIGS. 19A and 19B show the effects of the compound of Example 3 onpaclitaxel-induced neuropathy in rats. Group 1 of the rats receivedpaclitaxel for four days, as did the rats in FIG. 18. In groups 2 to 4,0.25 mL of the compound of Example 3 or the vehicle, a mixture of NMP,propylene glycol, and chromophore ELP (25%,25%,10%) in sterile waterwere administered 30 min prior to the administration of paclitaxel.Groups 2 and 4 continued to receive either the vehicle (group 2) or thecompound of Example 3 (group 4) daily for 11 more days. Paw withdrawalthresholds were determined daily in both hind paws of each animal usingcalibrated von Frey monofilaments according to an up-down procedure. Asshown, continued administration of 15 mg/kg of the compound of Example 3intraperitoneally (IP) daily completely prevented the development ofpaclitaxel-evoked mechano-allodynia. Administration of 15 mg/kg of thecompound of Example 3 IP for 4 days only did not prevent butsignificantly prevented the severity of paclitaxel-evokedmechano-allodynia

DETAILED DESCRIPTION OF THE INVENTION

Novel compounds presented include compounds defined by the structuralFormula II:

or a salt, ester or prodrug thereof, wherein:

-   -   R¹ is selected from the group consisting of NH₂, NHR³, NR³R⁴,        any carbon atom of which may be optionally substituted;

R² is selected from the group consisting of hydrogen, aryl, alkyl,cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon atom of which maybe optionally substituted; and

R³ and R⁴ are independently selected from the group consisting of aryl,alkyl, cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, and alkynyl, anycarbon atom of which may be optionally substituted,

and by the structural Formula IV:

or a salt, ester or prodrug thereof, wherein:

-   -   R¹ is selected from the group consisting of NH₂, NHR³, NR³R⁴,        any carbon atom of which may be optionally substituted;    -   R² is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any of carbon        atom of which may be optionally substituted;    -   R³ and R⁴ are independently selected from the group consisting        of aryl, alkyl, cycloalkyl, heterocycloalkyl, aralkyl, alkenyl,        and alkynyl, any carbon atom of which may be optionally        substituted; and    -   when R² is hydrogen, R¹ is not NH₂,

and by the structural Formula V:

or a salt, ester or prodrug thereof, wherein:

-   -   R¹ is selected from the group consisting of cyclohexylamino,        piperidinyl, and o-iodoanilino; and    -   R² is optionally substituted phenyl,        and by the structural Formula VI:

or a salt, ester or prodrug thereof, wherein:

-   -   q is an integer ranging from 0 to 2    -   X is absent or present and represents a —O—, —S—, —Se—, NR⁶,        SO—, —SO₂—,    -   Z represents a —O—, —S—, —SO—, —SO₂—, —Se— or NR⁷    -   R¹ is selected from the group consisting of NH₂, NHR⁴, NR⁴R⁵,        aryl, a heteroaryl alkyl, cycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted    -   R² is selected from the group consisting of hydrogen, alkyl,        cycloalkyl, aralkyl, alkenyl, and alkynyl an alkoxyl, any carbon        atom of which may be optionally substituted;    -   R³ is selected from the group consisting of aryl, a heteroaryl,        alkyl, cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted;    -   R⁴ and R⁵ vary independently and are selected from the group        consisting of aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted,    -   R⁶ is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted,    -   R⁷ is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted.

Novel compounds presented further include compounds defined by thestructural Formula VII:

or a salt, ester or prodrug thereof, wherein:

-   -   q is an integer ranging from 0 to 2    -   X is absent or present and represents a —O—, —S—, —Se—, NR⁶,        SO—, —SO₂—,    -   Z represents a —O—, —S—, —SO—, —SO₂—, —Se— or NR⁷    -   R¹ is selected from the group consisting of NH₂, NHR⁴, NR⁴R⁵,        aryl, a heteroaryl alkyl, cycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted    -   R² is selected from the group consisting of hydrogen, alkyl,        cycloalkyl, aralkyl, alkenyl, and alkynyl an alkoxyl, any carbon        atom of which may be optionally substituted;    -   R³ is selected from the group consisting of aryl, a heteroaryl,        alkyl, cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted;    -   R⁴ and R⁵ vary independently and are selected from the group        consisting of aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and        alkynyl, any carbon atom of which may be optionally substituted,    -   R⁶ is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted,    -   R³ and R⁶ taken together might form a cycloalkyl containing from        3 to 10 carbon atoms and eventually interrupted with one or more        hetero atoms or by —CO—, —SO—, —SO₂—, —CHOH— or —NR¹³—;    -   R⁷ is selected from the group consisting of hydrogen, aryl,        alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon        atom of which may be optionally substituted,    -   R⁸ and R⁹ are selected from the group consisting of hydrogen,        alkyl, an alkoxyl or taken together might form a carbonyl.

As used herein, the terms below have the meanings indicated.

The term “acyl,” as used herein, alone or in combination, refers to acarbonyl attached to an alkenyl, alkyl, aryl, cycloalkyl, heteroaryl,heterocyclyl, or any other moiety were the atom attached to the carbonylis carbon. An “acetyl” group refers to a —C(O)CH₃ group. An“alkylcarbonyl” or “alkanoyl” group refers to an alkyl group attached tothe parent molecular moiety through a carbonyl group. Examples of suchgroups include methylcarbonyl and ethylcarbonyl. Examples of acyl groupsinclude formyl, alkanoyl and aroyl.

The term “alkenyl,” as used herein, alone or in combination, refers to astraight-chain or branched-chain hydrocarbon radical having one or moredouble bonds and containing from 2 to 20, preferably 2 to 6, carbonatoms. Alkenylene refers to a carbon-carbon double bond system attachedat two or more positions such as ethenylene [(CH═CH—), (—C::C—)].Examples of suitable alkenyl radicals include ethenyl, propenyl,2-methylpropenyl, 1,4-butadienyl and the like.

The term “alkoxy,” as used herein, alone or in combination, refers to analkyl ether radical, wherein the term alkyl is as defined below.Examples of suitable alkyl ether radicals include methoxy, ethoxy,n-propoxy, isopropoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy,and the like.

The term “alkyl,” as used herein, alone or in combination, refers to astraight-chain or branched-chain alkyl radical containing from 1 to andincluding 20, preferably 1 to 10, and more preferably 1 to 6, carbonatoms. Alkyl groups may be optionally substituted as defined herein.Examples of alkyl radicals include methyl, ethyl, n-propyl, isopropyl,n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, iso-amyl, hexyl,octyl, noyl and the like. The term “alkylene,” as used herein, alone orin combination, refers to a saturated aliphatic group derived from astraight or branched chain saturated hydrocarbon attached at two or morepositions, such as methylene (—CH₂—).

The term “alkylamino,” as used herein, alone or in combination, refersto an alkyl group attached to the parent molecular moiety through anamino group. Suitable alkylamino groups may be mono- or dialkylated,forming groups such as, for example, N-methylamino, N-ethylamino,N,N-dimethylamino, N,N-ethylmethylamino and the like.

The term “alkylidene,” as used herein, alone or in combination, refersto an alkenyl group in which one carbon atom of the carbon-carbon doublebond belongs to the moiety to which the alkenyl group is attached.

The term “alkylthio,” as used herein, alone or in combination, refers toan alkyl thioether (R—S—) radical wherein the term alkyl is as definedabove and wherein the sulfur may be singly or doubly oxidized. Examplesof suitable alkyl thioether radicals include methylthio, ethylthio,n-propylthio, isopropylthio, n-butylthio, iso-butylthio, sec-butylthio,tert-butylthio, methanesulfonyl, ethanesulfinyl, and the like.

The term “alkynyl,” as used herein, alone or in combination, refers to astraight-chain or branched chain hydrocarbon radical having one or moretriple bonds and containing from 2 to 20, preferably from 2 to 6, morepreferably from 2 to 4, carbon atoms. “Alkynylene” refers to acarbon-carbon triple bond attached at two positions such as ethynylene(—C:::C—, —C═C—). Examples of alkynyl radicals include ethynyl,propynyl, hydroxypropynyl, butyn-1-yl, butyn-2-yl, pentyn-1-yl,3-methylbutyn-1-yl, hexyn-2-yl, and the like.

The terms “amido” and “carbamoyl,” as used herein, alone or incombination, refer to an amino group as described below attached to theparent molecular moiety through a carbonyl group, or vice versa. Theterm “C-amido” as used herein, alone or in combination, refers to a—C(═O)—NR₂ group with R as defined herein. The term “N-amido” as usedherein, alone or in combination, refers to a RC(═O)NH— group, with R asdefined herein. The term “acylamino” as used herein, alone or incombination, embraces an acyl group attached to the parent moietythrough an amino group. An example of an “acylamino” group isacetylamino (CH₃C(O)NH—).

The term “amino,” as used herein, alone or in combination, refers to—NRR′, wherein R and R′ are independently selected from the groupconsisting of hydrogen, alkyl, acyl, heteroalkyl, aryl, cycloalkyl,heteroaryl, and heterocycloalkyl, any of which may themselves beoptionally substituted.

The term “aryl,” as used herein, alone or in combination, means acarbocyclic aromatic system containing one, two or three rings whereinsuch rings may be attached together in a pendent manner or may be fused.The term “aryl” embraces aromatic radicals such as benzyl, phenyl,naphthyl, anthracenyl, phenanthryl, indanyl, indenyl, annulenyl,azulenyl, tetrahydronaphthyl, and biphenyl.

The term “arylalkenyl” or “aralkenyl,” as used herein, alone or incombination, refers to an aryl group attached to the parent molecularmoiety through an alkenyl group.

The term “arylalkoxy” or “aralkoxy,” as used herein, alone or incombination, refers to an aryl group attached to the parent molecularmoiety through an alkoxy group.

The term “arylalkyl” or “aralkyl,” as used herein, alone or incombination, refers to an aryl group attached to the parent molecularmoiety through an alkyl group.

The term “arylalkynyl” or “aralkynyl,” as used herein, alone or incombination, refers to an aryl group attached to the parent molecularmoiety through an alkynyl group.

The term “arylalkanoyl” or “aralkanoyl” or “aroyl,” as used herein,alone or in combination, refers to an acyl radical derived from anaryl-substituted alkanecarboxylic acid such as benzoyl, napthoyl,phenylacetyl, 3-phenylpropionyl (hydrocinnamoyl), 4-phenylbutyryl,(2-naphthyl)acetyl, 4-chlorohydrocinnamoyl, and the like.

The term “aryloxy,” as used herein, alone or in combination, refers toan aryl group attached to the parent molecular moiety through an oxy.

According to the present invention, the expression alkyl radicalsunderstood to mean a linear optionally branched and optionallyfluorinated radical. In certain embodiments, alkyl radicals having from6 to 12 carbon atoms are 2-Methyl-pentan-2-yl, 3,3-Dimethyl-butan-1-yl,hexyl, heptyl, octyl, nonyl, decyl, dodecyl. “Alkyl radicals” containingfrom 1 to 3 carbon atoms, are linear or branched radicals containing,respectively, from 1 to 3. Preferably, the alkyl radicals containingfrom 1 to 3 carbon atoms are methyl, ethyl, n-propyl, or 2-propylradicals. The expression “alkoxyl radical” is understood to mean aradical containing from 1 to 3 carbon atoms, such as methoxyl, ethoxyl,propyloxyl or isopropyloxyl radicals.

The term “aryl radical” means a phenyl or a naphthyl radical, eventuallymono- or disubstituted with at least one halogen, an alkyl containingfrom 1 to 3 carbon atoms, an alkoxyl, an aryl radical, a nitro function,a polyether radical, a heteroaryl radical, a benzoyl radical, an alkylester group, a carboxylic acid, a hydroxyl optionally protected with anacetyl or benzoyl group, or an amino function optionally protected withan acetyl or benzoyl group or optionally substituted with at least onealkyl containing from 1 to 12 carbon atoms.

The term “heteroaryl” means an aryl radical interrupted with one or morehetero atoms, such as a thiophenyl, thiazolyl or imidazolyl radical,optionally substituted with at least one halogen, an alkyl containingfrom 1 to 3 carbon atoms, an alkoxyl, an aryl radical, a nitro function,a polyether radical, a heteroaryl radical, a benzoyl radical, an alkylester group, a carboxylic acid, a hydroxyl optionally protected with anacetyl or benzoyl group, or an amino function optionally protected withan acetyl or benzoyl group or optionally substituted with at least onealkyl containing from 1 to 6 carbon atoms.

The term “polyether radical” means a polyether radical containing from 2to 6 carbon atoms interrupted with at least one oxygen atom, such asmethoxymethoxy, ethoxymethoxy or methoxyethoxymethoxy radicals.

The term “halogen atom” includes, but is not limited to, fluorine,chlorine or bromine atom.

The terms “benzo” and “benz,” as used herein, alone or in combination,refer to the divalent radical C₆H₄═ derived from benzene. Examplesinclude benzothiophene and benzimidazole.

The term “carbamate,” as used herein, alone or in combination, refers toan ester of carbamic acid (—NHCOO—) which may be attached to the parentmolecular moiety from either the nitrogen or acid end, and which may beoptionally substituted as defined herein.

The term “O-carbamyl” as used herein, alone or in combination, refers toa —OC(O)NRR′, group-with R and R′ as defined herein.

The term “N-carbamyl” as used herein, alone or in combination, refers toa ROC(O)NR′— group, with R and R′ as defined herein.

The term “carbonyl,” as used herein, when alone includes formyl [—C(O)H]and in combination is a —C(O)— group.

The term “carboxy,” as used herein, refers to —C(O)OH or thecorresponding “carboxylate” anion, such as is in a carboxylic acid salt.An “O-carboxy” group refers to a RC(O)O— group, where R is as definedherein. A “C-carboxy” group refers to a —C(O)OR groups where R is asdefined herein.

The term “cyano,” as used herein, alone or in combination, refers to—CN.

The term “cycloalkyl,” or, alternatively, “carbocycle,” as used herein,alone or in combination, refers to a saturated or partially saturatedmonocyclic, bicyclic or tricyclic alkyl radical wherein each cyclicmoiety contains from 3 to 12, preferably five to seven, carbon atom ringmembers and which may optionally be a benzo fused ring system which isoptionally substituted as defined herein. Examples of such cycloalkylradicals include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl, octahydronaphthyl, 2,3-dihydro-1H-indenyl, adamantyl andthe like. “Bicyclic” and “tricyclic” as used herein are intended toinclude both fused ring systems, such as decahydronapthalene,octahydronapthalene as well as the multicyclic (multicentered) saturatedor partially unsaturated type. The latter type of isomer is exemplifiedin general by, bicyclo[1,1,1]pentane, camphor, adamantane, andbicyclo[3,2,1]octane.

The term “ester,” as used herein, alone or in combination, refers to acarboxy group bridging two moieties linked at carbon atoms.

The term “ether,” as used herein, alone or in combination, refers to anoxy group bridging two moieties linked at carbon atoms.

The term “halo,” or “halogen,” as used herein, alone or in combination,refers to fluorine, chlorine, bromine, or iodine.

The term “haloalkoxy,” as used herein, alone or in combination, refersto a haloalkyl group attached to the parent molecular moiety through anoxygen atom.

The term “haloalkyl,” as used herein, alone or in combination, refers toan alkyl radical having the meaning as defined above wherein one or morehydrogens are replaced with a halogen. Specifically embraced aremonohaloalkyl, dihaloalkyl and polyhaloalkyl radicals. A monohaloalkylradical, for one example, may have an iodo, bromo, chloro or fluoro atomwithin the radical. Dihalo and polyhaloalkyl radicals may have two ormore of the same halo atoms or a combination of different halo radicals.Examples of haloalkyl radicals include fluoromethyl, difluoromethyl,trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl,pentafluoroethyl, heptafluoropropyl, difluorochloromethyl,dichlorofluoromethyl, difluoroethyl, difluoropropyl, dichloroethyl anddichloropropyl. “Haloalkylene” refers to a haloalkyl group attached attwo or more positions. Examples include fluoromethylene

(—CFH—), difluoromethylene (—CF₂—), chloromethylene (—CHCl—) and thelike.

The term “heteroalkyl,” as used herein, alone or in combination, refersto a stable straight or branched chain, or cyclic hydrocarbon radical,or combinations thereof, fully saturated or containing from 1 to 3degrees of unsaturation, consisting of the stated number of carbon atomsand from one to three heteroatoms selected from the group consisting ofO, N, and S, and wherein the nitrogen and sulfur atoms may optionally beoxidized and the nitrogen heteroatom may optionally be quaternized. Theheteroatom(s) O, N and S may be placed at any interior position of theheteroalkyl group. Up to two heteroatoms may be consecutive, such as,for example, —CH₂—NH—OCH₃.

The term “heteroaryl,” as used herein, alone or in combination, refersto 3 to 7 membered, preferably 5 to 7 membered, unsaturatedheteromonocyclic rings, or fused polycyclic rings in which at least oneof the fused rings is unsaturated, wherein at least one atom is selectedfrom the group consisting of O, S, and N. The term also embraces fusedpolycyclic groups wherein heterocyclic radicals are fused with arylradicals, wherein heteroaryl radicals are fused with other heteroarylradicals, or wherein heteroaryl radicals are fused with cycloalkylradicals. Examples of heteroaryl groups include pyrrolyl, pyrrolinyl,imidazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl,triazolyl, pyranyl, furyl, thienyl, oxazolyl, isoxazolyl, oxadiazolyl,thiazolyl, thiadiazolyl, isothiazolyl, indolyl, isoindolyl, indolizinyl,benzimidazolyl, quinolyl, isoquinolyl, quinoxalinyl, quinazolinyl,indazolyl, benzotriazolyl, benzodioxolyl, benzopyranyl, benzoxazolyl,benzoxadiazolyl, benzothiazolyl, benzothiadiazolyl, benzofuryl,benzothienyl, chromonyl, coumarinyl, benzopyranyl, tetrahydroquinolinyl,tetrazolopyridazinyl, tetrahydroisoquinolinyl, thienopyridinyl,furopyridinyl, pyrrolopyridinyl and the like. Exemplary tricyclicheterocyclic groups include carbazolyl, benzidolyl, phenanthrolinyl,dibenzofuranyl, acridinyl, phenanthridinyl, xanthenyl and the like.

The terms “heterocycloalkyl” and, interchangeably, “heterocyclyl,” asused herein, alone or in combination, each refer to a saturated,partially unsaturated, or fully unsaturated monocyclic, bicyclic, ortricyclic heterocyclic radical containing at least one, preferably 1 to4, and more preferably 1 to 2 heteroatoms as ring members, wherein eachsaid heteroatom may be independently selected from the group consistingof nitrogen, oxygen, and sulfur, and wherein there are preferably 3 to 8ring members in each ring, more preferably 3 to 7 ring members in eachring, and most preferably 5 to 6 ring members in each ring.“Heterocycloalkyl” and “heterocyclyl” are intended to include sulfones,sulfoxides, N-oxides of tertiary nitrogen ring members, and carbocyclicfused and benzo fused ring systems; additionally, both terms alsoinclude systems where a heterocycle ring is fused to an aryl group, asdefined herein, or an additional heterocycle group. Heterocyclyl groupsof the invention are exemplified by aziridinyl, azetidinyl,1,3-benzodioxolyl, dihydroisoindolyl, dihydroisoquinolinyl,dihydrocinnolinyl, dihydrobenzodioxinyl,dihydro[1,3]oxazolo[4,5-b]pyridinyl, benzothiazolyl, dihydroindolyl,dihy-dropyridinyl, 1,3-dioxanyl, 1,4-dioxanyl, 1,3-dioxolanyl,isoindolinyl, morpholinyl, piperazinyl, pyrrolidinyl,tetrahydropyridinyl, piperidinyl, thiomorpholinyl, and the like. Theheterocyclyl groups may be optionally substituted unless specificallyprohibited.

The term “hydrazinyl” as used herein, alone or in combination, refers totwo amino groups joined by a single bond, i.e., —N—N—.

The term “hydroxy,” as used herein, alone or in combination, refers to—OH.

The term “hydroxyalkyl,” as used herein, alone or in combination, refersto a hydroxy group attached to the parent molecular moiety through analkyl group.

The term “imino,” as used herein, alone or in combination, refers to═N—.

The term “iminohydroxy,” as used herein, alone or in combination, refersto ═N(OH) and ═N—O—.

The phrase “in the main chain” refers to the longest contiguous oradjacent chain of carbon atoms starting at the point of attachment of agroup to the compounds of this invention.

The term “isocyanato” refers to a —NCO group.

The term “isothiocyanato” refers to a —NCS group.

The phrase “linear chain of atoms” refers to the longest straight chainof atoms independently selected from carbon, nitrogen, oxygen andsulfur.

The term “lower,” as used herein, alone or in combination, meanscontaining from 1 to and including 6 carbon atoms.

The term “mercaptyl” as used herein, alone or in combination, refers toan RS— group, where R is as defined herein.

The term “nitro,” as used herein, alone or in combination, refers to—NO₂.

The terms “oxy” or “oxa,” as used herein, alone or in combination, referto —O—.

The term “oxo,” as used herein, alone or in combination, refers to ═O.

The term “perhaloalkoxy” refers to an alkoxy group where all of thehydrogen atoms are replaced by halogen atoms.

The term “perhaloalkyl” as used herein, alone or in combination, refersto an alkyl group where all of the hydrogen atoms are replaced byhalogen atoms.

The terms “sulfonate,” “sulfonic acid,” and “sulfonic,” as used herein,alone or in combination, refer the SO₃H group and its anion as thesulfonic acid is used in salt formation.

The term “sulfanyl,” as used herein, alone or in combination, refers to—S—.

The term “sulfinyl,” as used herein, alone or in combination, refers to—S(O)—.

The term “sulfonyl,” as used herein, alone or in combination, refers to—S(O)₂—.

The term “N-sulfonamido” refers to a RS(═O)₂NR′— group with R and R′ asdefined herein.

The term “S-sulfonamido” refers to a —S(═O)₂NRR′, group, with R and R′as defined herein.

The terms “thia” and “thio,” as used herein, alone or in combination,refer to a —S— group or an ether wherein the oxygen is replaced withsulfur. The oxidized derivatives of the thio group, namely sulfinyl andsulfonyl, are included in the definition of thia and thio.

The term “thiol,” as used herein, alone or in combination, refers to an—SH group.

The term “thiocarbonyl,” as used herein, when alone includes thioformyl—C(S)H and in combination is a —C(S)— group.

The term “N-thiocarbamyl” refers to an ROC(S)NR′— group, with R and R′as defined herein.

The term “O-thiocarbamyl” refers to a —OC(S)NRR′, group with R and R′ asdefined herein.

The term “thiocyanato” refers to a —CNS group.

The term “trihalomethanesulfonamido” refers to a X₃CS(O)₂NR— group withX is a halogen and R as defined herein.

The term “trihalomethanesulfonyl” refers to a X₃CS(O)₂— group where X isa halogen.

The term “trihalomethoxy” refers to a X₃CO— group where X is a halogen.

The term “trisubstituted silyl,” as used herein, alone or incombination, refers to a silicone group substituted at its three freevalences with groups as listed herein under the definition ofsubstituted amino. Examples include trimethysilyl,tert-butyldimethylsilyl, triphenylsilyl and the like.

Any definition herein may be used in combination with any otherdefinition to describe a composite structural group. By convention, thetrailing element of any such definition is that which attaches to theparent moiety. For example, the composite group alkylamido wouldrepresent an alkyl group attached to the parent molecule through anamido group, and the term alkoxyalkyl would represent an alkoxy groupattached to the parent molecule through an alkyl group.

When a group is defined to be “null,” what is meant is that said groupis absent.

The term “optionally substituted” means the anteceding group may besubstituted or unsubstituted. When substituted, the substituents of an“optionally substituted” group may include, without limitation, one ormore substituents independently selected from the following groups or aparticular designated set of groups, alone or in combination: loweralkyl, lower alkenyl, lower alkynyl, lower alkanoyl, lower heteroalkyl,lower heterocycloalkyl, lower haloalkyl, lower haloalkenyl, lowerhaloalkynyl, lower perhaloalkyl, lower perhaloalkoxy, lower cycloalkyl,phenyl, aryl, aryloxy, lower alkoxy, lower haloalkoxy, oxo, loweracyloxy, carbonyl, carboxyl, lower alkylcarbonyl, lower carboxyester,lower carboxamido, cyano, hydrogen, halogen, hydroxy, amino, loweralkylamino, arylamino, amido, nitro, thiol, lower alkylthio, arylthio,lower alkylsulfinyl, lower alkylsulfonyl, arylsulfinyl, arylsulfonyl,arylthio, sulfonate, sulfonic acid, trisubstituted silyl, N₃, SH, SCH₃,C(O)CH₃, CO₂CH₃, CO₂H, pyridinyl, thiophene, furanyl, lower carbamate,and lower urea. Two substituents may be joined together to form a fusedfive-, six-, or seven-membered carbocyclic or heterocyclic ringconsisting of zero to three heteroatoms, for example formingmethylenedioxy or ethylenedioxy. An optionally substituted group may beunsubstituted (e.g., —CH₂CH₃), fully substituted (e.g., —CF₂CF₃),monosubstituted (e.g., —CH₂CH₂F) or substituted at a level anywherein-between fully substituted and monosubstituted (e.g., —CH₂CF₃). Wheresubstituents are recited without qualification as to substitution, bothsubstituted and unsubstituted forms are encompassed. Where a substituentis qualified as “substituted,” the substituted form is specificallyintended. Additionally, different sets of optional substituents to aparticuar moiety may be defined as needed; in these cases, the optionalsubstitution will be as defined, often immediately following the phrase,“optionally substituted with.”

The term R or the term R′, appearing by itself and without a numberdesignation, unless otherwise defined, refers to a moiety selected fromthe group consisting of hydrogen, alkyl, cycloalkyl, heteroalkyl, aryl,heteroaryl and heterocycloalkyl, any of which may be optionallysubstituted. Such R and R′ groups should be understood to be optionallysubstituted as defined herein. Whether an R group has a numberdesignation or not, every R group, including R, R′ and R⁴¹ where n=(1,2, 3, . . . n), every substituent, and every term should be understoodto be independent of every other in terms of selection from a group.Should any variable, substituent, or term (e.g. aryl, heterocyclyl, R,etc.) occur more than one time in a formula or generic structure, itsdefinition at each occurrence is independent of the definition at everyother occurrence. Those of skill in the art will further recognize thatcertain groups may be attached to a parent molecule or may occupy aposition in a chain of elements from either end as written. Thus, by wayof example only, an unsymmetrical group such as —C(O)N(R)— may beattached to the parent moiety at either the carbon or the nitrogen.

Asymmetric centers exist in the compounds of the present invention.These centers are designated by the symbols “R” or “S,” depending on theconfiguration of substituents around the chiral carbon atom. It shouldbe understood that the invention encompasses all stereochemical isomericforms, including diastereomeric, enantiomeric, and epimeric forms, aswell as d-isomers and 1-isomers, and mixtures thereof. Individualstereoisomers of compounds can be prepared synthetically fromcommercially available starting materials which contain chiral centersor by preparation of mixtures of enantiomeric products followed byseparation such as conversion to a mixture of diastereomers followed byseparation or recrystallization, chromatographic techniques, directseparation of enantiomers on chiral chromatographic columns, or anyother appropriate method known in the art. Starting compounds ofparticular stereochemistry are either commercially available or can bemade and resolved by techniques known in the art. Additionally, thecompounds of the present invention may exist as geometric isomers. Thepresent invention includes all cis, trans, syn, anti, entgegen (E), andzusammen (Z) isomers as well as the appropriate mixtures thereof.Additionally, compounds may exist as tautomers; all tautomeric isomersare provided by this invention. Additionally, the compounds of thepresent invention can exist in unsolvated as well as solvated forms withpharmaceutically acceptable solvents such as water, ethanol, and thelike. In general, the solvated forms are considered equivalent to theunsolvated forms for the purposes of the present invention.

Optical isomers are compounds with the same molecular formula but differin the way they rotate plane polarized light. There are two kinds ofoptical isomers. The first optical isomer are compounds that are mirrorimages of one another but cannot be superimposed on each other. Theseisomers are called “enantiomers”. The second optical isomers aremolecules that are not mirror images but each molecule rotates planepolarized light and are considered optically active. Such molecules arecalled “diastereoisomers”. Diasteroisomers differ not only in the waythey rotate plane polarized light, but also their physical properties.The term “optical isomer” comprises more particularly the enantiomersand the diastereoisomers, in pure form or in the form of a mixture.

The term “bond” refers to a covalent linkage between two atoms, or twomoieties when the atoms joined by the bond are considered to be part oflarger substructure. A bond may be single, double, or triple unlessotherwise specified. A dashed line between two atoms in a drawing of amolecule indicates that an additional bond may be present or absent atthat position.

The term “combination therapy” means the administration of two or moretherapeutic agents to treat a therapeutic condition or disorderdescribed in the present disclosure. Such administration encompassesco-administration of these therapeutic agents in a substantiallysimultaneous manner, such as in a single capsule having a fixed ratio ofactive ingredients or in multiple, separate capsules for each activeingredient. In addition, such administration also encompasses use ofeach type of therapeutic agent in a sequential manner. In either case,the treatment regimen will provide beneficial effects of the drugcombination in treating the conditions or disorders described herein.

“Cannabinoid receptor modulator” is used herein to refer to a compoundthat exhibits an EC₅₀ or IC₅₀ with respect to a cannabinoid receptoractivity of no more than about 100 μM and more typically not more thanabout 50 μM, as measured in the cannabinoid receptor assay describedgenerally herein below. “EC₅₀” is that concentration of modulator whichactivates the activity of a cannabinoid receptor to half-maximal level.“IC₅₀” is that concentration of modulator which reduces the activity ofa cannabinoid receptor to half-maximal level. This test will be doneduring the exemplification period.

The term “modulator” described herein reflects any chemical compoundthat will act as full agonist, partial agonist, inverse agonist or as anantagonist at any known or yet to be discovered/identified cannabinoidreceptor.

Compounds described herein have been discovered to exhibit modulatoryactivity against cannabinoid receptors and exhibit an EC₅₀ or IC₅₀ withrespect to a cannabinoid receptor of no more than about 10 μM, morepreferably, no more than about 5 μM, even more preferably not more thanabout 1 μM, and most preferably, not more than about 200 nM, as measuredin the assays described herein.

The phrase “therapeutically effective” is intended to qualify the amountof active ingredients used in the treatment of a disease or disorder.This amount will achieve the goal of reducing or eliminating the saiddisease or disorder.

The term “therapeutically acceptable” refers to those compounds (orsalts, prodrugs, tautomers, zwitterionic forms, etc.) which are suitablefor use in contact with the tissues of patients without undue toxicity,irritation, and allergic response, are commensurate with a reasonablebenefit/risk ratio, and are effective for their intended use.

As used herein, reference to “treatment” of a patient is intended toinclude prophylaxis. The term “patient” means all mammals includinghumans. Examples of patients include humans, cows, dogs, cats, goats,sheep, pigs, and rabbits. Preferably, the patient is a human.

The term “prodrug” refers to a compound that is made more active invivo. Certain compounds of the present invention may also exist asprodrugs, as described in Hydrolysis in Drug and Prodrug Metabolism:Chemistry, Biochemistry, and Enzymology, Testa, Bernard and Wiley-VHCA,Zurich, Switzerland 2003. Prodrugs of the compounds described herein arestructurally modified forms of the compound that readily undergochemical changes under physiological conditions to provide the compound.Additionally, prodrugs can be converted to the compound by chemical orbiochemical methods in an ex vivo environment. For example, prodrugs canbe slowly converted to a compound when placed in a transdermal patchreservoir with a suitable enzyme or chemical reagent. Prodrugs are oftenuseful because, in some situations, they may be easier to administerthan the compound, or parent drug. They may, for instance, bebio-available by oral administration whereas the parent drug is not. Theprodrug may also have improved solubility in pharmaceutical compositionsover the parent drug. A wide variety of prodrug derivatives are known inthe art, such as those that rely on hydrolytic cleavage or oxidativeactivation of the prodrug. An example, without limitation, of a prodrugwould be a compound which is administered as an ester (the “prodrug”),but then is metabolically hydrolyzed to the carboxylic acid, the activeentity. Additional examples include peptidyl derivatives of a compound.

The compounds of the present invention can exist as therapeuticallyacceptable salts. The present invention includes compounds listed abovein the form of salts, in particular acid addition salts. Suitable saltsinclude those formed with both organic and inorganic acids. Such acidaddition salts will normally be pharmaceutically acceptable. However,salts of non-pharmaceutically acceptable salts may be of utility in thepreparation and purification of the compound in question. Basic additionsalts may also be formed and be pharmaceutically acceptable. For a morecomplete discussion of the preparation and selection of salts, refer toStahl, P. Heinrich, Pharmaceutical Salts: Properties, Selection, andUse, Wiley-VCHA, Zurich, Switzerland, 2002.

The term “therapeutically acceptable salt,” as used herein, representssalts or zwitterionic forms of the compounds of the present inventionwhich are water or oil-soluble or dispersible and therapeuticallyacceptable as defined herein. The salts can be prepared during the finalisolation and purification of the compounds or separately by reactingthe appropriate compound in the form of the free base with a suitableacid. Representative acid addition salts include acetate, adipate,alginate, L-ascorbate, aspartate, benzoate, benzenesulfonate (besylate),bisulfate, butyrate, camphorate, camphorsulfonate, citrate, digluconate,formate, fumarate, gentisate, glutarate, glycerophosphate, glycolate,hemisulfate, heptanoate, hexanoate, hippurate, hydrochloride,hydrobromide, hydroiodide, 2-hydroxyethansulfonate (isethionate),lactate, maleate, malonate, DL-mandelate, mesitylenesulfonate,methanesulfonate, naphthylenesulfonate, nicotinate,2-naphthalenesulfonate, oxalate, pamoate, pectinate, persulfate,3-phenylproprionate, phosphonate, picrate, pivalate, propionate,pyroglutamate, succinate, sulfonate, tartrate, L-tartrate,trichloroacetate, trifluoroacetate, phosphate, glutamate, bicarbonate,para-toluenesulfonate (p-tosylate), and undecanoate. Also, basic groupsin the compounds of the present invention can be quaternized withmethyl, ethyl, propyl, and butyl chlorides, bromides, and iodides;dimethyl, diethyl, dibutyl, and diamyl sulfates; decyl, lauryl,myristyl, and steryl chlorides, bromides, and iodides; and benzyl andphenethyl bromides. Examples of acids which can be employed to formtherapeutically acceptable addition salts include inorganic acids suchas hydrochloric, hydrobromic, sulfuric, and phosphoric, and organicacids such as oxalic, maleic, succinic, and citric. Salts can also beformed by coordination of the compounds with an alkali metal or alkalineearth ion. Hence, the present invention contemplates sodium, potassium,magnesium, and calcium salts of the compounds of the compounds of thepresent invention and the like.

Basic addition salts can be prepared during the final isolation andpurification of the compounds by reaction of a carboxy group with asuitable base such as the hydroxide, carbonate, or bicarbonate of ametal cation or with ammonia or an organic primary, secondary, ortertiary amine. The cations of therapeutically acceptable salts includelithium, sodium, potassium, calcium, magnesium, and aluminum, as well asnontoxic quaternary amine cations such as ammonium, tetramethylammonium,tetraethylammonium, methylamine, dimethylamine, trimethylamine,triethylamine, diethylamine, ethylamine, tributylamine, pyridine,N,N-dimethylaniline, N-methylpiperidine, N-methylmorpholine,dicyclohexylamine, procaine, dibenzylamine, N,N-dibenzylphenethylamine,1-ephenamine, and N,N-dibenzylethylenediamine. Other representativeorganic amines useful for the formation of base addition salts includeethylenediamine, ethanolamine, diethanolamine, piperidine, andpiperazine.

A salt of a compound can be made by reacting the appropriate compound inthe form of the free base with the appropriate acid. The novel compoundsdescribed in this patent could be prepared in a form of pharmaceuticallyacceptable salts that will be prepared from nontoxic inorganic ororganic bases including but not limited to aluminum, ammonium, calcium,copper, ferric, ferrous, lithium, magnesium, manganic salts, manganous,potassium, sodium, zinc, and the like. Salts derived frompharmaceutically acceptable organic non-toxic bases include salts ofprimary, secondary, and tertiary amines, substituted amines includingnaturally occurring substituted amines, cyclic amines, and basic ionexchange resins, such as argmine, betaine, caffeine, choline,ethylamine, 2-diethylaminoethano, 1,2-dimethylaminoethanol,ethanolamine, ethylenediamine, N-ethyl-morpholine, N-ethylpiperidine,glucamine, glucosamine, histidine, hydrabamine, isopropylamine, lysine,methylglucamine, morpholine, piperazine, piperidine, polyamine resins,procaine, purines, theobromine, triethylamine, trimethylamine,trishydroxylmethyl amino methane, tripropyl amine, and tromethamine.

If the novel compounds described in this patent are basic, salts couldbe prepared in a form of pharmaceutically acceptable salts that will beprepared from nontoxic inorganic or organic acids including but notlimited to hydrochloric, hydrobromic, phosphoric, sulfuric, tartaric,citric, acetic, fumaric, alkylsulphonic, naphthalenesulphonic,para-toluenesulphonic, camphoric acids, benzenesulfonic, benzoic,camphorsulfonic, citric, ethanesulfonic, gluconic, glutamic, isethonic,lactic, maleic, malic, mandelic, methanesulfonic, mucic, nitric, pamoic,pantothenic, phosphoric, and succinic.

While it may be possible for the compounds of the subject invention tobe administered as the raw chemical, it is also possible to present themas a pharmaceutical formulation. Accordingly, the subject inventionprovides a pharmaceutical formulation comprising a compound or apharmaceutically acceptable salt, ester, prodrug or solvate thereof,together with one or more pharmaceutically acceptable carriers thereofand optionally one or more other therapeutic ingredients. The carrier(s)must be “acceptable” in the sense of being compatible with the otheringredients of the formulation and not deleterious to the recipientthereof. Proper formulation is dependent upon the route ofadministration chosen. Any of the well-known techniques, carriers, andexcipients may be used as suitable and as understood in the art; e.g.,in Remington's Pharmaceutical Sciences. The pharmaceutical compositionsof the present invention may be manufactured in a manner that is itselfknown, e.g., by means of conventional mixing, dissolving, granulating,dragee-making, levigating, emulsifying, encapsulating, entrapping orcompression processes.

The formulations include those suitable for oral, parenteral (includingsubcutaneous, intradermal, intramuscular, intravenous, intraarticular,and intramedullary), intraperitoneal, transmucosal, transdermal, rectaland topical (including dermal, buccal, sublingual and intraocular)administration although the most suitable route may depend upon forexample the condition and disorder of the recipient. The formulationsmay conveniently be presented in unit dosage form and may be prepared byany of the methods well known in the art of pharmacy. All methodsinclude the step of bringing into association a compound of the subjectinvention or a pharmaceutically acceptable salt, ester, prodrug orsolvate thereof (“active ingredient”) with the carrier which constitutesone or more accessory ingredients. In general, the formulations areprepared by uniformly and intimately bringing into association theactive ingredient with liquid carriers or finely divided solid carriersor both and then, if necessary, shaping the product into the desiredformulation.

Formulations of the present invention suitable for oral administrationmay be presented as discrete units such as capsules, cachets or tabletseach containing a predetermined amount of the active ingredient; as apowder or granules; as a solution or a suspension in an aqueous liquidor a non-aqueous liquid; or as an oil-in-water liquid emulsion or awater-in-oil liquid emulsion. The active ingredient may also bepresented as a bolus, electuary or paste.

Pharmaceutical preparations which can be used orally include tablets,push-fit capsules made of gelatin, as well as soft, sealed capsules madeof gelatin and a plasticizer, such as glycerol or sorbitol. Tablets maybe made by compression or molding, optionally with one or more accessoryingredients. Compressed tablets may be prepared by compressing in asuitable machine the active ingredient in a free-flowing form such as apowder or granules, optionally mixed with binders, inert diluents, orlubricating, surface active or dispersing agents. Molded tablets may bemade by molding in a suitable machine a mixture of the powdered compoundmoistened with an inert liquid diluent. The tablets may optionally becoated or scored and may be formulated so as to provide slow orcontrolled release of the active ingredient therein. All formulationsfor oral administration should be in dosages suitable for suchadministration. The push-fit capsules can contain the active ingredientsin admixture with filler such as lactose, binders such as starches,and/or lubricants such as talc or magnesium stearate and, optionally,stabilizers. In soft capsules, the active compounds may be dissolved orsuspended in suitable liquids, such as fatty oils, liquid paraffin, orliquid polyethylene glycols. In addition, stabilizers may be added.Dragee cores are provided with suitable coatings. For this purpose,concentrated sugar solutions may be used, which may optionally containgum arabic, talc, polyvinyl pyrrolidone, carbopol gel, polyethyleneglycol, and/or titanium dioxide, lacquer solutions, and suitable organicsolvents or solvent mixtures. Dyestuffs or pigments may be added to thetablets or dragee coatings for identification or to characterizedifferent combinations of active compound doses.

One example of a formulation appropriate for administration through anoral route comprises 0.60 g of the compound of Example 16, 10.00 g ofNMP, 64.40 g of LABRAFIL® M1944 CS, and 25.00 g of LABRASOL®.

The compounds may be formulated for parenteral administration byinjection, e.g., by bolus injection or continuous infusion. Formulationsfor injection may be presented in unit dosage form, e.g., in ampoules orin multi-dose containers, with an added preservative. The compositionsmay take such forms as suspensions, solutions or emulsions in oily oraqueous vehicles, and may contain formulatory agents such as suspending,stabilizing and/or dispersing agents. The formulations may be presentedin unit-dose or multi-dose containers, for example sealed ampoules andvials, and may be stored in powder form or in a freeze-dried(lyophilized) condition requiring only the addition of the sterileliquid carrier, for example, saline or sterile pyrogen-free water,immediately prior to use. Extemporaneous injection solutions andsuspensions may be prepared from sterile powders, granules and tabletsof the kind previously described.

Formulations for parenteral administration include aqueous andnon-aqueous (oily) sterile injection solutions of the active compoundswhich may contain antioxidants, buffers, bacteriostats and solutes whichrender the formulation isotonic with the blood of the intendedrecipient; and aqueous and non-aqueous sterile suspensions which mayinclude suspending agents and thickening agents. Suitable lipophilicsolvents or vehicles include fatty oils such as sesame oil, or syntheticfatty acid esters, such as ethyl oleate or triglycerides, or liposomes.Aqueous injection suspensions may contain substances which increase theviscosity of the suspension, such as sodium carboxymethyl cellulose,sorbitol, or dextran. Optionally, the suspension may also containsuitable stabilizers or agents which increase the solubility of thecompounds to allow for the preparation of highly concentrated solutions.

One example of a formulation appropriate for administration through aparenteral route comprises 1.00 g of the compound of Example 3, 30.00 gof NMP, 30.00 g of propylene glycol, 10.00 g of CREMOPHOR® ELP, 10.00 gof EtOH (95%), and 19.00 g of saline solution.

In addition to the formulations described previously, the compounds mayalso be formulated as a depot preparation. Such long acting formulationsmay be administered by implantation (for example subcutaneously orintramuscularly) or by intramuscular injection. Thus, for example, thecompounds may be formulated with suitable polymeric or hydrophobicmaterials (for example as an emulsion in an acceptable oil) or ionexchange resins, or as sparingly soluble derivatives, for example, as asparingly soluble salt.

For buccal or sublingual administration, the compositions may take theform of tablets, lozenges, pastilles, or gels formulated in conventionalmanner. Such compositions may comprise the active ingredient in aflavored basis such as sucrose and acacia or tragacanth.

The compounds may also be formulated in rectal compositions such assuppositories or retention enemas, e.g., containing conventionalsuppository bases such as cocoa butter, polyethylene glycol, or otherglycerides.

Compounds of the present invention may be administered topically, thatis by non-systemic administration. This includes the application of acompound of the present invention externally to the epidermis or thebuccal cavity and the instillation of such a compound into the ear, eyeand nose, such that the compound does not significantly enter the bloodstream. In contrast, systemic administration refers to oral,intravenous, intraperitoneal and intramuscular administration.

Formulations suitable for topical administration include solid, liquidor semi-liquid preparations suitable for penetration through the skin tothe site of inflammation such as gels, liniments, lotions, creams,ointments or pastes, and drops suitable for administration to the eye,ear or nose. The active ingredient may comprise, for topicaladministration, from 0.001% to 10% w/w, for instance from 1% to 2% byweight of the formulation. It may however comprise as much as 10% w/wbut preferably will comprise less than 5% w/w, more preferably from0.01% to 1% w/w of the formulation.

Via the topical route, the pharmaceutical composition according to theinvention is more particularly intended for treating the skin and mucousmembranes and may be in the form of liquid or semi liquid such asointments, creams or in the form of solid such as powders. It may alsobe in the form of suspensions such as polymeric microspheres or polymerpatches and hydrogels allowing a controlled release. This topicalcomposition may be in anhydrous form, in aqueous form or in the form ofan emulsion. The compounds are used topically at a concentrationgenerally of between 0.001% and 10% by weight and preferably between0.01% and 1% by weight, relative to the total weight of the composition.

One example of a formulation appropriate for administration through atopical route comprises 3.00 g of the compound of Example 13, 35.00 g ofNMP, 25.00 g of LABRASOL®, 15.00 g of oleic acid, 12.00 g of COMPRITOL®888 ATO, and 10.00 g of EtOH.

The compounds presented herein may also find an application incosmetics, in particular in body and hair hygiene and more particularlyfor regulating and/or restoring skin lipid metabolism.

Cosmetic use of a composition comprising, in a physiologicallyacceptable support, at least one of the compounds described herein forbody or hair hygiene are presented. The cosmetic composition, in acosmetically acceptable support, at least one compound and/or an opticalor geometrical isomer thereof or a salt thereof, and may be in the formof liquid or semi liquid such as ointments, creams or in the form ofsolid such as powders. It may also be in the form of suspensions such aspolymeric microspheres or polymer patches and hydrogels allowing acontrolled release. This topical composition may be in anhydrous form,in aqueous form or in the form of an emulsion. The concentration ofcompound in the cosmetic composition is between 0.001% and 5% by weightrelative to the total weight of the composition. Finally, a subject ofthe present invention is a cosmetic process for enhancing the skin,which consists in applying to the skin a composition comprising at leastone compound presented herein.

For administration by inhalation, the compounds according to theinvention are conveniently delivered from an insufflator, nebulizerpressurized packs or other convenient means of delivering an aerosolspray. Pressurized packs may comprise a suitable propellant such asdichlorodifluoromethane, trichlorofluoromethane,dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In thecase of a pressurized aerosol, the dosage unit may be determined byproviding a valve to deliver a metered amount. Alternatively, foradministration by inhalation or insufflation, the compounds according tothe invention may take the form of a dry powder composition, for examplea powder mix of the compound and a suitable powder base such as lactoseor starch. The powder composition may be presented in unit dosage form,in for example, capsules, cartridges, gelatin or blister packs fromwhich the powder may be administered with the aid of an inhalator orinsufflator.

Preferred unit dosage formulations are those containing an effectivedose, as herein below recited, or an appropriate fraction thereof, ofthe active ingredient.

It should be understood that in addition to the ingredients particularlymentioned above, the formulations of this invention may include otheragents conventional in the art having regard to the type of formulationin question, for example those suitable for oral administration mayinclude flavoring agents.

The compounds of the invention may be administered orally or viainjection at a dose of from 0.1 to 500 mg/kg per day. The dose range foradult humans is generally from 5 mg to 2 g/day. Tablets or other formsof presentation provided in discrete units may conveniently contain anamount of compound of the invention which is effective at such dosage oras a multiple of the same, for instance, units containing 5 mg to 500mg, usually around 10 mg to 200 mg.

Certain compounds according to the invention can be administered at adaily dose of about 0.001 mg/kg to 100 mg/kg of body weight, in 1 to 3dosage intakes. Further, certain compounds can be used systemically, ata concentration generally of between 0.001% and 10% by weight andpreferably between 0.01% and 1% by weight, relative to the weight of thecomposition.

The amount of active ingredient that may be combined with the carriermaterials to produce a single dosage form will vary depending upon thehost treated and the particular mode of administration.

The compounds of the subject invention can be administered in variousmodes, e.g. orally, topically, or by injection. The precise amount ofcompound administered to a patient will be the responsibility of theattendant physician. The specific dose level for any particular patientwill depend upon a variety of factors including the activity of thespecific compound employed, the age, body weight, general health, sex,diets, time of administration, route of administration, rate ofexcretion, drug combination, the precise disorder being treated, and theseverity of the indication or condition being treated. Also, the routeof administration may vary depending on the condition and its severity.

In certain instances, it may be appropriate to administer at least oneof the heterocyclic compounds described herein (or a pharmaceuticallyacceptable salt, ester, or prodrug thereof) in combination with anothertherapeutic agent. By way of example only, if one of the side effectsexperienced by a patient upon receiving one of the compounds herein ishypertension, then it may be appropriate to administer ananti-hypertensive agent in combination with the initial therapeuticagent. Or, by way of example only, the therapeutic effectiveness of oneof the compounds described herein may be enhanced by administration ofan adjuvant (i.e., by itself the adjuvant may only have minimaltherapeutic benefit, but in combination with another therapeutic agent,the overall therapeutic benefit to the patient is enhanced). Or, by wayof example only, the benefit of experienced by a patient may beincreased by administering one of the compounds described herein withanother therapeutic agent (which also includes a therapeutic regimen)that also has therapeutic benefit. By way of example only, in atreatment for pain involving administration of one of the compoundsdescribed herein, increased therapeutic benefit may result by alsoproviding the patient with another therapeutic agent for pain. In anycase, regardless of the disease, disorder or condition being treated,the overall benefit experienced by the patient may simply be additive ofthe two therapeutic agents or the patient may experience a synergisticbenefit.

Specific, non-limiting examples of possible combination therapiesinclude use of the compounds of the invention together with inert oractive compounds, or other drugs including wetting agents, flavourenhancers, preserving agents, stabilizers, humidity regulators, pHregulators, osmotic pressure modifiers, emulsifiers, UV-A and UV-Bscreening agents, antioxidants, depigmenting agents such as hydroquinoneor kojic acid, emollients, moisturizers, for instance glycerol, PEG 400,or urea, antiseborrhoeic or antiacne agents, such as benzoyl peroxide,antibiotics, for instance erythromycin and tetracyclines, antifungalagents such as ketoconazole, agents for promoting regrowth of the hair,for instance Minoxidil (2,4-diamino-6-piperidinopyrimidine 3-oxide),non-steroidal anti-inflammatory agents, carotenoids, and especiallyp-carotene, antipsoriatic agents such as anthralin and its derivatives,retinoids, i.e. RAR or RXR receptor ligands, corticosteroids oroestrogens, alpha-hydroxy acids and a-keto acids or derivatives thereof,such as lactic acid, malic acid, citric acid, and also the salts, amidesor esters thereof, or p-hydroxy acids or derivatives thereof, such assalicylic acid and the salts, amides or esters thereof, ion-channelblockers such as potassium-channel blockers, or alternatively, moreparticularly for the pharmaceutical compositions, in combination withmedicaments known to interfere with the immune system, anticonvulsantagents include, and are not limited to, topiramate, analogs oftopiramate, carbamazepine, valproic acid, lamotrigine, gabapentin,phenyloin and the like and mixtures or pharmaceutically acceptable saltsthereof. Needless to say, a person skilled in the art will take care toselect the other compound(s) to be added to these compositions such thatthe advantageous properties intrinsically associated with theheterocyclic compound are not, or are not substantially, adverselyaffected by the envisaged addition.

In any case, the multiple therapeutic agents (at least one of which is acompound of the present invention) may be administered in any order oreven simultaneously. If simultaneously, the multiple therapeutic agentsmay be provided in a single, unified form, or in multiple forms (by wayof example only, either as a single pill or as two separate pills). Oneof the therapeutic agents may be given in multiple doses, or both may begiven as multiple doses. If not simultaneous, the timing between themultiple doses may be any duration of time ranging from a few minutes tofour weeks.

Thus, in another aspect, methods for treating cannabinoidreceptor-mediated disorders in a human or animal subject in need of suchtreatment are presented herein, the methods comprising the step ofadministering to a subject in need thereof an amount of a heterocycliccompound effective to reduce or prevent a disorder in combination withat least one additional agent for the treatment of said disorder that isknown in the art.

In a related aspect, therapeutic compositions having at least one novelheterocyclic compound described herein can be administered incombination with one or more additional agents for the treatment ofcannabinoid-mediated disorders.

Furthermore, methods of treatment of certain diseases and indications ina human or animal subject in need of such treatment are provided herein.Heterocyclic compounds described herein can be used alone or incombination with other agents and compounds in the treatment ofneuropathic pain, addiction (including nicotine, cocaine, opioids,hashish, marijuana, alcohol dependence, food), cancer (includingmelanoma, lymphomas, and gliomas), inflammation including autoimmuneinflammation, cardiovascular disease, liver fibrosis, obesity,osteoporosis and other bone disease. Additional indications for use ofthe compounds disclosed herein include acne, psoriasis, allergic contactdermatitis, anxiety, spasticity and tremor, bladder dysfunctions,prevention of miscarriage and ectopic pregnancy, Tourette's, Parkinson'sdisease, stroke, glaucoma and other diseases of the eye includingintraocular pressure, diarrhea and nausea. Each such treatment describedabove includes the step of administering to a subject in need thereof atherapeutic effective amount of the heterocyclic compound describedherein to reduce or prevent such disease or indication.

Besides being useful for human treatment, the compounds and formulationsof the present invention are also useful for veterinary treatment ofcompanion animals, exotic animals and farm animals, including mammals,rodents, and the like. More preferred animals include horses, dogs, andcats. These heterocyclic compounds are also helpful in neuronal growthand development.

Therefore, the compounds described herein may be used alone or incombination with another agent or compound in methods for treating,ameliorating or preventing a syndrome, disorder or disease in whichcannabinoid receptor is involved, including, but not limited to, ocularcomplaint such as glaucoma, pain, controlling appetite, regulatingmetabolism, diabetes, social and mood disorders, seizure-relateddisorders, substance abuse disorders, learning, cognition and/or memorydisorders, bowel disorders, gastrointestinal disorders, respiratorydisorders, locomotor activity disorders, movement disorders, immunedisorders or inflammation disorders, and controlling organ contractionand muscle spasm.

The compounds presented herein may be also useful in enhancing learning,cognition and/or memory, regulating cell growth, providingneuroprotection and the like. The compounds presented herein may also beused for treating dermatological complaints associated with akeratinization disorder relating to cell differentiation andproliferation, especially for treating acne, for treating otherdermatological complaints with or without cell proliferation disorder,and especially all forms of psoriasis, for treating all dermal orepidermal proliferations, for preventing or treating cicatrizationdisorders, in the treatment of dermatological or general complaints withan immunological component, in the treatment of skin disorders caused byexposure to UV radiation, and also for combating sebaceous functiondisorders, for repairing or combating ageing of the skin, for preventingor treating cicatrization disorders, in the treatment of pigmentationdisorders.

Historically, cannabinoid preparations have been used for medicinal andrecreational purposes for many centuries. Cannabinoids are present inthe hemp Cannabis sativa L. Identification of the main activeingredient, tetrahydrocannabinol (Δ9-THC) has been done in 1964. GaoniY, Mechoulam R, Isolation, Structure, and Partial Synthesis of an ActiveConstituent of Hashish, J Am Chem Soc 1964, 86:1646-7. Theendocannabinoid system was elucidated in the early 1990's. Currently,two receptors belonging to the GPCR family CB1 and CB2, five endogenouslipid ligands and the enzymes involved in their syntheses and metabolismhave been identified. Matsuda L A, Lolait S J, Brownstein M J, Young AC, Bonner T I, Structure Of A Cannabinoid Receptor And FunctionalExpression Of The Cloned Cdna, Nature 1990, 346:561-4.

CB1 is abundantly expressed in the central nervous system with highestdensity level in the basal ganglia, cerebellum, hippocampus and cortexas well as in the peripheral nervous system such as testis, eye, urinarybladder and adipocyte. CB2 is mainly expressed in the immune tissues andcells such as the thymus, marrow, spleen, pancreas and in glioma andskin tumor cells.

CB2 receptors and their gene transcripts have been recently demonstratedas widely distributed in the brain. The multifocal expression of CB2immunoreactivity in brain suggests that CB2 receptors play a role in thebrain and may be involved in depression and substance abuse. See e.g.,Onaivi E S, Ishiguro H, Gong J-P, Patel S, Perchuk A, Meozzi P A, MyersL, Mora Z, Tagliaferro P, Gardner E, Brusco A, Akinshola B E, Liu Q-R,Hope B, Iwasaki S, Arinami T, Teasenfitz L, Uhl G R, Discovery of thePresence and Functional Expression of Cannabinoid CB2 Receptors inBrain, Ann NY Acad Sci 2006, 1074:514-536; Berghuis P, Rajnicek A M,Morozov Y M, Ross R A, Mulder J, Urban G M, Monory K, Marsicano G,Matteoli M, Canty A, Irving A J, Katona I, Yanagawa Y, Rakic P, Lutz B,Mackie K, Harkany T, Hardwiring the Brain: Endocannabinoids ShapeNeuronal Connectivity, Science 2007, 316:1212-1216; Kalsi V, Fowler C J,Therapy Insight: Bladder Dysfunction Associated With Multiple Sclerosis,Nat Clin Pract Urol 2005, 2:492-501; Kathuria S, Gaetani S, Fegley D,Valino F, Duranti A, Tontini A, Mor M, Tarzia G, Rana G L, Calignano A,Giustino A, Tattoli M, Palmery M, Cuomo V, Piomelli D, Modulation ofAnxiety Through Blockade of Anandamide Hydrolysis, Nat Med 2003, 9:76-81; Baker D, Pryce G, Croxford J L, Brown P, Pertwee R G, Huffman JW, Layward L, Cannabinoids Control Spasticity and Tremor in a MultipleSclerosis Model, Nature 2000, 404:84-87. Furthermore, theendocannabinoid system has been implicated in allergic contactdermatitis. Karsak M, Gaffal E, Date R, Wang-Eckhardt L, Rehnelt J,Petrosino S, Starowicz K, Steuder R, Schlicker E, Cravatt B, MechoulamR, Buettner R, Werner S, Di Marzo V, Tuting T, Zimmer A, Attenuation ofAllergic Contact Dermatitis Through the Endocannabinoid System, Science2007, 316:1494-7.

In addition, studies provide support for the role of cannabinoid systemin several physiological functions including food consumption and bodyweight, in which CB1 receptor activation leads to increased foodconsumption and weight gain. Fride, E., Endocannabinoids in the CentralNervous System—an Overview, Prostaglandins Leukot Essent Fatty Acids2002, 66:221-33. Subsequently, CB1 receptor blockade reduces foodconsumption and leads to weight loss. Van Gaal L F, Rissanen A M, ScheenA J, Ziegler O, Rossner S, Effects Of The Cannabinoid-1 Receptor BlockerRimonabant On Weight Reduction And Cardiovascular Risk Factors InOverweight Patients: 1-Year Experience From The RIO-Europe Study, TheLancet 2005, 365:1389-1397.

Modulators of CB1/CB2 receptors have been used in different clinical orpreclinical studies. Steffens S, Veillard N R, Arnaud C, Pelli G, BurgerF, Staub C, Zimmer A, Frossard J-L, Mach F, Low Dose Oral CannabinoidTherapy Reduces Progression of Atherosclerosis in Mice, Nature 2005,434:782-786. For example, CB1 agonists have been used for treatment ofnausea, Tourette's, Parkinson's disease, glaucoma, cancer, diarrhoea,and stroke. Guzman M, Cannabinoids: Potential Anticancer Agents, NatureReviews Cancer 2003, 3:745-755. Further, CB2 agonists have been used fortreatment pain, gliomas, lymphomas, and inflammation. Maresz K, Pryce G,Ponomarev E D, Marsicano G, Croxford J L, Shriver L P, Ledent C, ChengX, Carrier E J, Mann M K, Giovannoni G, Pertwee R G, Yamamura T, BuckleyN E, Hillard C J, Lutz B, Baker D, Dittel B N, Direct Suppression of CNSAutoimmune Inflammation Via the Cannabinoid Receptor CB1 on Neurons andCB2 on Autoreactive T Cells, Nat Med 2007, 13: 492-497.

Moreover, CB1 antagonists have been used for treatment obesity andaddiction. Crowley V E F, Yeo G S H, O'Rahilly S, Obesity Therapy:Altering the Energy Intake-and-Expenditure Balance Sheet, Nature ReviewsDrug Discovery 2002, 1:276-286; Trang T, Sutak M, Jhamandas K,Involvement of Cannabinoid (CB1)-Receptors in the Development andMaintenance of Opioid Tolerance, Neuroscience 2007, 146:1275-1288;Teixeira-Clerc F, Julien B, Grenard P, Van Nhieu J T, Deveaux V, Li L,Serriere-Lanneau V, Ledent C, Mallat A, Lotersztajn S, CB1 CannabinoidReceptor Antagonism: A New Strategy For the Treatment of Liver Fibrosis,Nat Med 2006, 12:671-676. For example, the CB1 antagonist SR141716Areduces food intake in mice. Di Marzo V, Goparaju S K, Wang L, Liu J,Batkai S, Jarai Z, Fezza F, Miura G I, Palmiter R D, Sugiura T, Kunos G,Leptin-Regulated Endocannabinoids Are Involved In Maintaining FoodIntake, Nature 2001, 410:822-5. Also, CB1 cannabinoid antagonists havebeen cited to treat drug addiction. Maldonado R, Valverde O, BerrenderoF, Involvement Of The Endocannabinoid System In Drug Addiction, TrendsNeurosci 2006, 29:225-32. Cannabinoids attenuate deep tissuehyperalgesia produced by both cancer and inflammatory conditions. Kehl LJ, Hamamoto D T, Wacnik P W, Croft D L, Norsted B D, Wilcox G L, SimoneD A, A Cannabinoid Agonist Differentially Attenuates Deep TissueHyperalgesia In Animal Models Of Cancer And Inflammatory Muscle Pain,Pain 2003, 103:175-86. Cannabinoids also have a good potential for thetreatment osteoporosis and other bone diseases. Idris A I, van 't Hof RJ, Greig I R, Ridge S A, Baker D, Ross R A, Ralston S H, Regulation OfBone Mass, Bone Loss And Osteoclast Activity By Cannabinoid Receptors,Nat Med 2005, 11:774-9. Cannabinoids are able to reduce intraocularpressure. Szczesniak A M, Kelly M E, Whynot S, Shek P N, Hung O. Ocularhypotensive effects of an intratracheally delivered liposomaldelta9-tetrahydrocannabinol preparation in rats, J Ocul Pharmacol Ther.2006 June; 22(3):160-7. CB1 has also been shown to be involved inectopic pregnancy in mice. Wang H, Guo Y, Wang D, Kingsley P J, MarnettL J, Das S K, DuBois R N, Dey S K, Aberrant Cannabinoid SignalingImpairs Oviductal Transport of Embryos, Nat Med 2004, 10:1074-1080.

Certain published data demonstrate that human keratinocytes partake inthe peripheral endocannabinoid system. CB1 receptors have beenimplicated in epidermal differentiation and skin development. MaccarroneM, Di Rienzo M, Battista N, Gasperi V, Guerrieri P, Rossi A,Finazzi-Agro A, The Endocannabinoid System In Human Keratinocytes.Evidence That Anandamide Inhibits Epidermal Differentiation Through CB1Receptor-Dependent Inhibition Of Protein Kinase C, Activation Protein-1,And Transglutaminase, J Biol Chem 2003, 278:33896-903. Hence,cannabinoid modulator can be useful in the treatment of skin diseases.

Recently it has been shown that show that cannabinoids inhibitkeratinocyte proliferation, and therefore support a potential role forcannabinoids in the treatment of psoriasis. Wilkinson J D, Williamson EM, Cannabinoids Inhibit Human Keratinocyte Proliferation Through ANon-CB1/CB2 Mechanism And Have A Potential Therapeutic Value In TheTreatment Of Psoriasis, J Dermatol Sci 2007, 45:87-92. Cannabinoidreceptors have also been described as novel targets for the treatment ofmelanoma. Blazquez C, Carracedo A, Barrado L, Real P J, Fernandez-Luna JL, Velasco G, Malumbres M, Guzman M, Cannabinoid Receptors As NovelTargets For The Treatment Of Melanoma, Faseb J 2006, 20:2633-5.

General Synthetic Methods for Preparing Compounds

The following schemes can be used to practice the present invention.

General synthetic scheme for compounds of Formula I, Formula II, FormulaIII, Formula IV and Formula V:

The compounds of Formula I, Formula II, Formula III, Formula IV andFormula V may be obtained by alkylation of the corresponding iodophenola (Z═O, iodoaniline, Z═N, may be used for indole analogues) using a basesuch as cesium carbonate or sodium hydride, for example, to provide thephenolic ether b. The phenolic ether is subjected to a transition metal(such as nickel or palladium) catalyzed cyclization in the presence of ahydride donor such as ammonium formate or an organometallic derivativesin order to obtain the cyclized 2,3-dihydrobenzofuran (or indole)product c. After saponification of the ester to yield to thecorresponding carboxylic acid d, a peptide coupling procedure using, forexample, HATU, DIEA affords the corresponding amide derivatives e(R₁═NHR). Using the Weinreb amide (R₁═NHOMe) allows for organometallicadditions, such as hexyl lithium for example, affording ketone productsf in which R₁ is, for example, an alkyl or aryl group.

The invention is further illustrated by the following examples.

Example 1 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(2-iodo-phenyl)-amide

A) 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester

To a solution of methyl 3-hydroxy-4-iodobenzoate (1.5 g, 5.4 mmol) inanhydrous methyl ethyl ketone (60 mL) was added finely powderedPotassium carbonate (1.49 g, 10.78 mmol) followed by3-bromo-2-methyl-propene (0.81 mL, 1.1 g, 8.15 mmol). The reactionmixture was heated at 70° C. for 4 h. The mixture was diluted filtrated,washed with water and dried over MgSO4. Evaporation of the solvent andof the remaining bromopropene in vacuo afforded the requisite alkylatedester as a yellow oil. M: 1.4 g, Yield: 78%

NMR (CDCl₃, 1H): 1.90 (3H, d, J=1.2 Hz), 194 (3H, s), 4.56 (2H, s), 5.06(1H, d, J=1.2 Hz), 5.25 (1H, d, J=1.2 Hz), 7.38 (1H, dd, J=8.1 Hz, J=1.8Hz), 7.44 (1H, d, J=1.8 Hz), 7.88 (1H, d, J=1.8 Hz)

B) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid methylester

To a solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) obtained in Example 4(A), in DMF (15 mL) were addedPotassium carbonate (379 mg, 2.74 mmol), Tetrabutylammonium chloride(380 mg, 1.37 mmol), Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5mL) and Phenylboronic acid (200 mg, 1.64 mmol). The resulting mixturewas stirred for 3 h at 115° C., cooled to room temperature, filteredover silica, washed with water, dried over MgSO4 and concentrated.Column chromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded 368 mg(95%) of the title compound as a slightly brown oil which crystallize.Mp:52° C.

NMR (CDCl₃, 1H): 1.38 (3H, s), 2.86 (1H, d, J=14 Hz), 2.93 (1H, d, J=14Hz), 3.89 (3H, s), 4.12 (1H, d, J=8.7 Hz), 4.55 (1H, d, J=8.7 Hz),6.93-6.98 (3H, m), 7.22-7.24 (3H, m), 7.38 (1H, d, J=1.2 Hz), 7.59 (1H,dd, J1=7.5 Hz, J2=1.2 Hz).

C) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid

A mixture of 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester (300 mg, 1.06 mmol) obtained in Example 4(B), sodiumhydroxide (260 mg, 6.5 mmol), ethanol (10 ml) and water (1 ml) intetrahydrofuran (10 ml), is stirred for 12 h at room temperature. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (Na2SO4), and concentrated in a rotary evaporator. Theproduct is obtained as a white solid (300 mg, 100%). Mp: 165° C.

NMR (CDCl₃, ¹H): 1.39 (3H, s), 2.87 (1H, d, J=14 Hz), 2.93 (1H, d, J=14Hz), 4.14 (1H, d, J=8.7 Hz), 4.57 (1H, d, J=8.7 Hz), 6.96-7.00 (3H, m),7.22-7.25 (3H, m), 7.45 (1H, d, J=1.2 Hz), 7.65 (1H, dd, J1=7.8 Hz,J2=1.2 Hz).

D) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(2-iodo-phenyl)-amide

To a stirred suspension of3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (80 mg, 0.3mmol) and 2-Iodoaniline (72 mg, 0.33 mmol) in dichloromethane (3 mL) andDMF (2 mL) were addedO-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (125 mg, 0.33 mmol) and then a solution ofN,N-diisopropylethylamine (58 mg, 78 μL, 0.45 mmol, mL) in DMF (1 mL).The reaction mixture was stirred at ambient temperature for 18 h. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (MgSO₄), and concentrated to give the amide which ispurified by flash chromatography (AcOEt/heptane: 4/6). The column waschosen too small and a bigger column was chosen (AcOEt/heptane: 4/6) toafford 22 mg of the desired amid as a pale yellow solid (16%).

NMR (CDCl₃, ¹H): 1.44 (3H, s), 2.92 (1H, d, J=13.2 Hz), 2.98 (1H, d,J=13.2 Hz), 4.21 (1H, d, J=8.7 Hz), 4.62 (1H, d, J=8.7 Hz), 6.98-7.00(21-1, m), 7.07 (111, d, J=7.8 Hz), 7.26-728 (4H, m), 7.46 (1H, dd,J1=4.5 Hz, J2=8.4 Hz), 7.61 (1H, d, J=1.2 Hz), 7.85 (1H, dd, J1=1.2 Hz,J2=7.8 Hz), 8.46 (1H, dd, J1=1.5 Hz, J2=8.4 Hz), 8.74 (1H, dd, J1=1.5Hz, J2=4.5 Hz).

Example 2 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidcyclohexylamide

A) 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester

To a solution of methyl 3-hydroxy-4-iodobenzoate (1.5 g, 5.4 mmol) inanhydrous methyl ethyl ketone (60 mL) was added finely powderedPotassium carbonate (1.49 g, 10.78 mmol) followed by3-bromo-2-methyl-propene (0.81 mL, 1.1 g, 8.15 mmol). The reactionmixture was heated at 70° C. for 4 h. The mixture was diluted filtrated,washed with water and dried over MgSO4. Evaporation of the solvent andof the remaining bromopropene in vacuo afforded the requisite alkylatedester as a yellow oil. M: 1.4 g, Yield: 78%

NMR (CDCl₃, 1H): 1.90 (3H, d, J=1.2 Hz), 3.94 (3H, s), 4.56 (2H, s),5.06 (1H, d, J=1.2 Hz), 5.25 (1H, d, J=1.2 Hz), 7.38 (1H, dd, J=8.1 Hz,J=1.8 Hz), 7.44 (1H, d, J=1.8 Hz), 7.88 (1H, d, J=1.8 Hz)

B) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid methylester

To a solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) obtained in Example 4(A), in DMF (15 mL) were addedPotassium carbonate (379 mg, 2.74 mmol), Tetrabutylammonium chloride(380 mg, 1.37 mmol), Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5mL) and Phenylboronic acid (200 mg, 1.64 mmol). The resulting mixturewas stirred for 3 h at 115° C., cooled to room temperature, filteredover silica, washed with water, dried over MgSO4 and concentrated.Column chromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded 368 mg(95%) of the title compound as a slightly brown oil which crystallize.Mp:52° C.

NMR (CDCl₃, 1H): 1.38 (3H, s), 2.86 (1H, d, J=14 Hz), 2.93 (1H, d, J=14Hz), 3.89 (3H, s), 4.12 (1H, d, J=8.7 Hz), 4.55 (1H, d, J=8.7 Hz),6.93-6.98 (3H, m), 7.22-7.24 (3H, m), 7.38 (1H, d, J=1.2 Hz), 7.59 (1H,dd, J1=7.5 Hz, J2=1.2 Hz).

C) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid

A mixture of 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester (300 mg, 1.06 mmol) obtained in Example 4(B), sodiumhydroxide (260 mg, 6.5 mmol), ethanol (10 ml) and water (1 ml) intetrahydrofuran (10 ml), is stirred for 12 h at room temperature. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (Na2SO4), and concentrated in a rotary evaporator. Theproduct is obtained as a white solid (300 mg, 100%). Mp: 165° C.

NMR (CDCl₃, ¹H): 1.39 (3H, s), 2.87 (1H, d, J=14 Hz), 2.93 (1H, d, J=14Hz), 4.14 (1H, d, J=8.7 Hz), 4.57 (1H, d, J=8.7 Hz), 6.96-7.00 (3H, m),7.22-7.25 (3H, m), 7.45 (1H, d, J=1.2 Hz), 7.65 (1H, dd, J1=7.8 Hz,J2=1.2 Hz).

D) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidcyclohexylamide

To a stirred suspension of3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (80 mg, 0.3mmol) previously obtained in Example 4(C) and Cyclohexylamine (33 mg, 38μL, 0.33 mmol) in dichloromethane (3 mL) and DMF (2 mL) were added0-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (125 mg, 0.33 mmol) and then a solution ofN,N-diisopropylethylamine (58 mg, 78 pt, 0.45 mmol, mL) in DMF (1 mL).The reaction mixture was stirred at ambient temperature for 18 h. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (MgSO₄), and concentrated to give the amide which ispurified by flash chromatography (AcOEt/heptane: 4/6) to afford 70 mg ofa white solid (yield: 67%).

NMR (CDCl₃, ¹H): 1.15-1.28 (3H, m), 1.34-1.46 (5H, m), 1.6-1.78 (3H, m),1.99-2.04 (2H, m), 2.00-2.04 (2H, m), 2.86 (1H, d, J=13.2 Hz), 2.92 (1H,d, J=13.2 Hz), 3.96 (1H, m), 4.11 (1H, d, J=8.7 Hz), 4.54 (1H, d, J=8.7Hz), 5.85 (1H, m), 6.92 (1H, d, J=7.5 Hz), 6.96-6.99 (2H, m), 7.10 (1H,d, J=1.5 Hz), 7.22-728 (4H, m).

Example 3 3-benzyl-3-methyl-2,3-dihydrobenzofuran-6-carboxylicacid-piperidine amide

To a stirred suspension of the3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (80 mg, 0.3mmol) previously obtained in Example 1(C) and Piperidine (28 mg, 33 μL,0.33 mmol) in dichloromethane (3 mL) and DMF (2 mL) were addedO-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (125 mg, 0.33 mmol) and then a solution ofN,N-diisopropylethylamine (58 mg, 78 μL, 0.45 mmol, mL) in DMF (1 mL).The reaction mixture was stirred at ambient temperature for 18 h. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (MgSO₄), and concentrated to give the amide which ispurified by flash chromatography (AcOEt/heptane: 4/6) to afford 50 mg ofa white solid (yield: 50%).

NMR (CDCl₃, ¹H): 1.36 (3H, s), 1.54-1.67 (6H, m), 2.85 (1H, d, J=13.2Hz), 2.90 (1H, d, J=13.2 Hz), 3.35 (2H, m), 3.68 (2H, m), 4.09 (1H, d,J=8.7 Hz), 4.53 (1H, d, J=8.7 Hz), 6.75 (1H, m), 6.88 (1H, dd, 31=7.5Hz, J2=1.2 Hz), 6.94 (1H, d, J=7.5 Hz), 7.00 (2H, m), 7.21-7.24 (3H, m).

Example 4 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylicacid-o-iodoanilide

A) 4-Hydroxy-3-iodo-benzoic acid

4-Hydroxybenzoic acid (0.037 mol, 5.1 g) was dissolved in 100 mL ofmethanol. One equivalent each of sodium iodide (0.037 mol, 5.54 g) andsodium hydroxide (0.037 mol, 1.48 g) was added, and the solution wascooled to 0° C. Aqueous sodium hypochlorite (64 ml, 4.0% NaOCl) wasadded dropwise over 75 min at 0-3° C. As each drop hit the solution, ared color appeared and faded almost instantly. The resulting colorlessslurry was stirred for 1 h at 0-2° C. and then was treated with 40 mL of10% aqueous sodium thiosulfate. The mixture was acidified by 4M aqueousHCl. A product crystallized and was filtered off to afford 1.1 g. Ethylacetate (250 mL) was added, and the layers were separated. The organiclayer was washed with brine (240 mL), water and then dried over MgSO₄.After evaporation of the solvent, 4.3 g of a white powder was obtained.The aqueous phase was acidified to pH 1. Ethyl acetate (250 mL) wasadded, and the layers were separated. The organic layer was washed withbrine (240 mL), water and then dried over MgSO₄. After evaporation ofthe solvent, 8.22 g of a white powder was obtained.

B) Methyl 4-hydroxy-3-iodobenzoate

A solution of 3-iodo-4-Hydroxybenzoic acid (7.25 g, 27.4 mmol) andsulfuric acid (1.9 ml, 36 mmol) in methanol is stirred at 55° C. for 6hours. TLC (dichloromethane): 30% of starting material. The solution isstirred 12 h at room temperature. TLC (dichloromethane): 10% of startingmaterial and stirred at 55° C. for 2 h. After cooling, ethyl acetate(200 mL) was added and the mixture was adjusted to pH 3 using sodiumbicarbonate. The organic layer was washed two times with water and thendried over MgSO₄. Filtration and rotary evaporation at 40° C. afforded awhite solid. The solid was triturated with hexane, filtered off anddried under reduced pressure. M=4.47 g. Yield: 59%.

C) 3-Iodo-4-(2-methyl-allyloxy)-benzoic acid methyl ester

To a solution of methyl 4-hydroxy-3-iodobenzoate (1.5 g, 5.4 mmol) inanhydrous methyl ethyl ketone (60 mL) was added finely powderedPotassium carbonate (1.49 g, 10.78 mmol) followed by3-bromo-2-methyl-propene (0.81 mL, 1.1 g, 8.15 mmol). The reactionmixture was heated at 70° C. for 4 h. The mixture was diluted filtrated,washed with water and dried over MgSO₄. Evaporation of the solvent andof the remaining bromopropene in vacuo afforded the requisite alkylatedester as a yellow oil. M: 1.77, Yield: 98%.

1H(CDCl3): 1.88 (3H, d, J=1.2 Hz), 3.09 (3H, s), 4.54 (2H, s), 5.04 (1H,d, J=1.2 Hz), 5.19 (1H, d, J=1.2 Hz), 6.80 (1H, d, J=8.7 Hz), 7.98 (1H,dd, J=8.7 Hz, J=1.8 Hz), 8.46 (1H, d, J=1.8 Hz)

D) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid methylester

To a solution of 3-Iodo-4-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) in DMF (15 mL) were added Potassium carbonate (379mg, 2.74 mmol), Tetrabutylammonium chloride (380 mg, 1.37 mmol), asolution of Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5 mL) andPhenylboronic acid (200 mg, 1.64 mmol). The resulting mixture wasstirred for 3 h at 115° C., cooled to room temperature, filtered oversilica, washed with water, dryed over MgSO4 and concentrated. Columnchromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded 202 mg (52%)of the title compound as a slight brown oil.

NMR (CDCl₃, ¹H): 1.39 (3H, s), 2.87 (1H, d, J=15 Hz), 2.93 (1H, d, J=15Hz), 3.89 (3H, s), 4.13 (1H, d, J=9 Hz), 4.59 (1H, d, J=9 Hz), 6.74 (1H,d, J=8.4 Hz), 6.99 92H, m), 7.22-7.24 (3H, m), 7.72 (1H, d, J=1.8 Hz),7.89 (1H, dd, J1=8.4 Hz, J2=1.8 Hz).

E) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid

A mixture of 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acidmethyl ester (125 mg, 0.44 mmol), sodium hydroxide (120 mg, 3 mmol),ethanol (6 mL) and water (1 mL) in tetrahydrofuran (6 mL), is stirredfor 12 h at room temperature. The reaction medium is acidified by addinga 1.2 M hydrochloric acid solution and extracted with ethyl acetate. Theorganic phase is washed with water, dried (Na₂SO₄), and concentrated ina rotary evaporator. The product is obtained as slightly brown oil (116mg, 97%).

NMR (CDCl₃, ¹H): 1.30 (3H, s), 2.77 (1H, d, J=13 Hz), 2.83 (1H, d, J=13Hz), 4.05 (1H, d, J=9 Hz), 4.52 (1H, d, J=9 Hz), 6.67 (1H, d, J=8.4 Hz),6.86-6.89 (2H, m), 7.11-7.14 (3H, m), 7.69 (1H, d, J=1.8 Hz), 7.89 (1H,dd, J1=8.4 Hz, J2=1.8 Hz), 11.41 (1H).

F) -Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylicacid-o-iodoanilide

To a stirred suspension of3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid (60 mg, 0.225mmol) and 2-Iodoaniline (54 mg, 0.25 mmol) in dichloromethane (2 mL) andDMF (1 mL) were added O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) (94 mg, 0.25 mmol) anda solution of N,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF(1 mL). The reaction mixture was stirred at ambient temperature for 18h. The reaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (MgSO₄), and concentrated to give the amide which ispurified by flash chromatography (AcOEt/heptane: 3/7) to afford 10 mg(10%) of a slightly brown solid.

NMR (CDCl3, 1H): 1.45 (3H, s), 2.88 (1H, d, J=13.5 Hz), 2.98 (1H, d,J=13.5 Hz), 4.24 (1H, d, J=9 Hz), 4.70 (1H, d, J=9 Hz), 6.89 (1H, d,J=8.4 Hz), 6.96-7.02 (3H, m), 7.22-7.28 (3H, m), 7.46 (2H, dd, J1=4.5Hz, J2=8.4 Hz), 7.89 (1H, d, 2.1 Hz), 8.16 (1H, dd, J=1.8 Hz, j=8.4 Hz),8.47 (1H, dd, J1=1.2 Hz, J2=8.4 Hz).

Example 5 3-benzyl-3-methyl-2,3-dihydrobenzofuran-5-carboxylicacid-cyclohexylamide

A) 4-Hydroxy-3-iodo-benzoic acid

4-Hydroxybenzoic acid (0.037 mol, 5.1 g) was dissolved in 100 mL ofmethanol. One equivalent each of sodium iodide (0.037 mol, 5.54 g) andsodium hydroxide (0.037 mol, 1.48 g) was added, and the solution wascooled to 0° C. Aqueous sodium hypochlorite (64 ml, 4.0% NaOCl) wasadded dropwise over 75 min at 0-3° C. As each drop hit the solution, ared color appeared and faded almost instantly. The resulting colorlessslurry was stirred for 1 h at 0-2° C. and then was treated with 40 mL of10% aqueous sodium thiosulfate. The mixture was acidified by 4M aqueousHCl. A product crystallized and was filtered off to afford 1.1 g. Ethylacetate (250 mL) was added, and the layers were separated. The organiclayer was washed with brine (240 mL), water and then dried over MgSO₄.After evaporation of the solvent, 4.3 g of a white powder was obtained.The aqueous phase was acidified to pH 1. Ethyl acetate (250 mL) wasadded, and the layers were separated. The organic layer was washed withbrine (240 mL), water and then dried over MgSO₄. After evaporation ofthe solvent, 8.22 g of a white powder was obtained.

B) Methyl 4-hydroxy-3-iodobenzoate

A solution of 3-iodo-4-Hydroxybenzoic acid (7.25 g, 27.4 mmol) andsulfuric acid (1.9 ml, 36 mmol) in methanol is stirred at 55° C. for 6hours. TLC (dichloromethane): 30% of starting material. The solution isstirred 12 h at room temperature. TLC (dichloromethane): 10% of startingmaterial and stirred at 55° C. for 2 h. After cooling, ethyl acetate(200 mL) was added and the mixture was adjusted to pH 3 using sodiumbicarbonate. The organic layer was washed two times with water and thendried over MgSO₄. Filtration and rotary evaporation at 40° C. afforded awhite solid. The solid was triturated with hexane, filtered off anddried under reduced pressure. M=4.47 g. Yield: 59%.

C) 3-Iodo-4-(2-methyl-allyloxy)-benzoic acid methyl ester

To a solution of methyl 4-hydroxy-3-iodobenzoate (1.5 g, 5.4 mmol) inanhydrous methyl ethyl ketone (60 mL) was added finely powderedPotassium carbonate (1.49 g, 10.78 mmol) followed by3-bromo-2-methyl-propene (0.81 mL, 1.1 g, 8.15 mmol). The reactionmixture was heated at 70° C. for 4 h. The mixture was diluted filtrated,washed with water and dried over MgSO₄. Evaporation of the solvent andof the remaining bromopropene in vacuo afforded the requisite alkylatedester as a yellow oil. M: 1.77, Yield: 98%.

1H(CDCl₃): 1.88 (3H, d, J=1.2 Hz), 3.09 (3H, s), 4.54 (2H, s), 5.04 (1H,d, J=1.2 Hz), 5.19 (1H, d, J=1.2 Hz), 6.80 (1H, d, J=8.7 Hz), 7.98 (1H,dd, J=8.7 Hz, J=1.8 Hz), 8.46 (1H, d, J=1.8 Hz)

D) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid methylester

To a solution of 3-Iodo-4-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) in DMF (15 mL) were added Potassium carbonate (379mg, 2.74 mmol), Tetrabutylammonium chloride (380 mg, 1.37 mmol), asolution of Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5 mL) andPhenylboronic acid (200 mg, 1.64 mmol). The resulting mixture wasstirred for 3 h at 115° C., cooled to room temperature, filtered oversilica, washed with water, dryed over MgSO4 and concentrated. Columnchromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded 202 mg (52%)of the title compound as a slight brown oil.

NMR (CDCl₃, ¹H): 1.39 (3H, s), 2.87 (1H, d, J=15 Hz), 2.93 (1H, d, J=15Hz), 3.89 (3H, s), 4.13 (1H, d, J=9 Hz), 4.59 (1H, d, J=9 Hz), 6.74 (1H,d, J=8.4 Hz), 6.99 92H, m), 7.22-7.24 (3H, m), 7.72 (1H, d, J=1.8 Hz),7.89 (1H, dd, J1=8.4 Hz, J2=1.8 Hz).

E) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid

A mixture of 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acidmethyl ester (125 mg, 0.44 mmol), sodium hydroxide (120 mg, 3 mmol),ethanol (6 mL) and water (1 mL) in tetrahydrofuran (6 mL), is stirredfor 12 h at room temperature. The reaction medium is acidified by addinga 1.2 M hydrochloric acid solution and extracted with ethyl acetate. Theorganic phase is washed with water, dried (Na₂SO₄), and concentrated ina rotary evaporator. The product is obtained as slightly brown oil (116mg, 97%).

NMR (CDCl₃, 1H): 1.30 (3H, s), 2.77 (1H, d, J=13 Hz), 2.83 (1H, d, J=13Hz), 4.05 (1H, d, J=9 Hz), 4.52 (1H, d, J=9 Hz), 6.67 (1H, d, J=8.4 Hz),6.86-6.89 (2H, m), 7.11-7.14 (3H, m), 7.69 (1H, d, J=1.8 Hz), 7.89 (1H,dd, J1=8.4 Hz, J2=1.8 Hz), 11.41 (1H).

F) 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acidcyclohexylamide

To a stirred suspension of the3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 4(E) and Cyclohexylamine (25 mg, 29tit, 0.25 mmolin dichloromethane (2 mL) and DMF (1 mL) were addedO-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and thenN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol). The reactionmixture was stirred at ambient temperature for 18 h. The reaction mediumis acidified by adding a 1.2 M hydrochloric acid solution and extractedwith ethyl acetate. The organic phase is washed with water, dried(MgSO₄), and concentrated to give the amide as a white solid. The solidwas washed with a mixture of heptane and dichloromethane 9/1 to afford38 mg of a white solid (Yield: 48%). The filtrate was concentrated andthe white solid obtained was washed with a mixture of heptane anddichloromethane (9/1) to afford 13 mg of a white solid.

NMR (CDCl₃, 1H): 1.19-1.28 (3H, m), 1.3-1.45 (9H, m), 2.02 (2H, m), 2.86(1H, d, J=13.5 Hz), 2.92 (1H, d, J=13.5 Hz), 3.91-3.97 (2H, m), 4.14(1H, d, J=8.7 Hz), 4.57 (1H, d, J=8.7 Hz), 5.73 (1H, m), 6.75 (1H, d,J=8.4 Hz), 6.96-6.99 (2H, m), 7.23-7.26 (4H, m), 7.56 (1H, dd, J=1.8 Hz,j=8.4 Hz).

Example 6 3-benzyl-3-methyl-2,3-dihydrobenzofuran-5-carboxylicacid-piperidine amide

To a stirred suspension of the3-Benzyl-3-methyl-2,3-dihydro-benzofuran-5-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 4(E) and Piperidine (21 mg, 25 μL0.25 mmol) in dichloromethane (2 mL) and DMF (1 mL) were addedO-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL). Thereaction mixture was stirred at ambient temperature for 18 h. Thereaction medium is acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase is washedwith water, dried (MgSO₄), and concentrated to give the amide which ispurified by flash chromatography (AcOEt/heptane: 4/6) to afford 54 mg(71.5%) of the desired amide as a colorless oil.

NMR (CDCl₃, 1H): 1.37 (3H, s), 1.58-1.69 (6H, m), 2.86 (1H, d, J=13.5Hz), 2.92 (1H, d, J=13.5 Hz), 3.51 (4H, broad), 4.10 (1H, d, J=8.7 Hz),4.54 (1H, d, J=8.7 Hz), 6.73 (1H, d, J=8.1 Hz), 6.98-7.03 (3H, m),7.18-7.23 (4H, m).

Example 7 3-benzyl-3-methyl-2,3-dihydrobenzofuran-5-carboxylic acid(2,2-dimeth yl-propyl)-amide

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C), neopentylamine (0.25 mmol) indichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ0.98 (s, 9H), 1.37 (s, 6H), 2.86 (d, 1H), 2.91 (d, 1H), 3.26 (d, 2H),4.12 (d, 1H), 4.54 (d, 1H), 6.08 (br s, 1H), 6.95 (d, 1H), 6.98-7.00 (m,2H), 7.12 (d, 1H), 7.23-7.25 (m, 3H), 7.29 (dd, 1H).

Example 8 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(tetrahydro-pyran-4-ylmethyl)-amide

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C),4-(Aminomethyl)tetrahydropyran (0.25 mmol) in dichloromethane (2 mL) andDMF (1 mL), O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.30-1.45 (m, 9H), 1.65 (d, 2H), 2.86 (d, 1H), 2.91 (d, 1H), 3.23-3.40(m, 4H), 3.98 (dd, 2H), 4.12 (d, 1H), 4.54 (d, 1H), 6.23 (br s, 1H),6.94 (d, 1H), 6.98-7.00 (m, 2H), 7.12 (d, 1H), 7.23-7.25 (m, 3H), 7.28(dd, 1H).

Example 9

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C), Morpholine (0.25 mmol) indichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.36 (s, 6H), 2.86 (d, 1H), 2.90 (d, 1H), 3.46-3.72 (br m, 8H), 4.10 (d,1H), 4.54 (d, 1H), 6.77 (d, 1H), 6.90 (dd, 1H), 6.95 (d, 1H), 7.00 (dd,1H), 7.22-7.26 (m, 3H).

Example 10 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(2,2-dimethyl-propyl)-methyl-amide

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C), N-tert-Butylmethylamine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.35 (s, 6H), 1.49 (s, 9H), 2.85-2.88 (m, 5H), 4.08 (d, 1H), 4.51 (d,1H), 6.78 (d, 1H), 6.89 (d, 1H), 6.93 (dd, 1H), 6.97-7.00 (m, 2H),7.20-7.24 (m, 3H).

Example 11 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid((S)-1,2,2-trimethyl-propyl)-amide

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C),(S)-(+)-3,3-Dimethyl-2-butylamine (0.25 mmol) in dichloromethane (2 mL)and DMF (1 mL), O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ0.97 (s, 9H), 1.15 (d, 3H), 1.36 (s, 3H), 2.86 (d, 1H), 2.93 (d, 1H),4.06-4.13 (m, 2H), 4.54 (d, 1H), 6.93 (d, 1H), 6.99 (dd, 1H), 7.10 (dd,1H), 7.23-7.29 (m, 5H).

Example 12 3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid((R)-1,2,2-trimethyl-propyl)-amide

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid (60 mg, 0.225mmol) previously obtained in Example 1(C),(R)-(+3,3-Dimethyl-2-butylamine (0.25 mmol) in dichloromethane (2 mL)and DMF (1 mL), O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil.

Example 13[3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-yl]-piperidin-1-yl-methanone

A) 3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester

A solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) in DMF (15 mL) were added Potassium carbonate (379mg, 2.74 mmol), Tetrabutylammonium chloride (380 mg, 1.37 mmol),Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5 mL) and4-Chlorophenylboronic acid, (256 mg, 1.64 mmol) was submitted tomicrowave irradiation at 140° C. for 21 minutes. The resulting mixturewas filtered over silica, washed with water, dried over MgSO4 andconcentrated. Column chromatography (silica gel, heptane/CH₂Cl₂: 5/5)afforded 160 mg (37%) of the title compound as a slightly brown oil.

B) 3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid

A mixture of3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester (100 mg, 0.32 mmol), sodium hydroxide (100 mg, 2.5 mmol),ethanol (3 ml) and water (0.5 ml) in tetrahydrofuran (4 ml), was stirredfor 12 h at room temperature. The reaction medium was acidified byadding a 1.2 M hydrochloric acid solution and extracted with ethylacetate. The organic phase was washed with water, dried (Na₂SO₄), andconcentrated in a rotary evaporator. The product was obtained as a whitesolid. (M: 89 mg, 92%).

C)[3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-yl]-piperidin-1-yl-methanone

In a manner similar to that of Example 6, by reacting3-(4-Chloro-benzyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(0.225 mmol) previously obtained in Example 13(B), Piperidine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.36 (s, 3H), 2.84 (t, 1H), 3.33 (br s, 2H), 3.67 (br s, 2H), 4.10 (d,1H), 4.48 (d, 1H), 6.74 (s, 1H), 6.88-6.91 (m, 4H), 7.2 (d, 2H).

Example 14(3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

A) 3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid methyl ester

A solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) in DMF (15 mL) were added Potassium carbonate (379mg, 2.74 mmol), Tetrabutylammonium chloride (380 mg, 1.37 mmol),Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5 mL) and1-Naphthylboronic acid, (282 mg, 1.64 mmol) was submitted to microwaveirradiation at 100° C. for 10 minutes and as the reaction was notcompleted at 150° C. for 15 minutes. The resulting mixture was filteredover silica, washed with water, dried over MgSO4 and concentrated.Column chromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded 196 mg(43%) of the title compound as a slightly brown oil.

B) 3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid

A mixture of3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid methyl ester (150 mg, 0.45 mmol), sodium hydroxide (150 mg, 3.75mmol), ethanol (5 ml) and water (1 ml) in tetrahydrofuran (5 ml), wasstirred for 12 h at room temperature. The reaction medium was acidifiedby adding a 1.2 M hydrochloric acid solution and extracted with ethylacetate. The organic phase was washed with water, dried (Na₂SO₄), andconcentrated in a rotary evaporator. The product was obtained as a brownoil (M: 128 mg, 89%).

C)(3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

In a manner similar to that of Example 6, by3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid (0.225 mmol) previously obtained in Example 14(B), Piperidine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzothazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.43 (s, H), 3.30 (br d, 3H), 3.50 (d, 1H), 3.67 (br s, 2H), 4.09 (d,1H), 4.58 (d, 1H), 6.74 (m, 2H), 7.19 (dd, 1H), 7.32-7.43 (m, 3H), 7.75(d, 1H), 7.81 (d, 1H).

Example 15(3-Methyl-3-naphthalen-2-ylmethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

A) 3-Methyl-3-naphthalen-2-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid methyl ester

A solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(455 mg, 1.37 mmol) in DMF (15 mL) were added Potassium carbonate (379mg, 2.74 mmol), Tetrabutylammonium chloride (380 mg, 1.37 mmol),Palladium acetate (25.6 mg, 0.136 mmol) in DMF (5 mL) and2-Naphthylboronic acid, (282 mg, 1.64 mmol) was submitted to microwaveirradiation at 150° C. for 16 minutes. The resulting mixture wasfiltered over silica, washed with water, dried over MgSO₄ andconcentrated. Column chromatography (silica gel, heptane/CH₂Cl₂: 4/6)afforded 100 mg (22%) of the title compound as a slightly brown oilwhich crystallized.

B) 3-Methyl-3-naphthalen-2-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid

A mixture of PhD001.125 (80 mg, 0.24 mmol), sodium hydroxide (90 mg,2.25 mmol), ethanol (4 ml) and water (1 ml) in tetrahydrofuran (4 ml),was stirred for 12 h at room temperature. The reaction medium wasacidified by adding a 1.2 M hydrochloric acid solution and extractedwith ethyl acetate. The organic phase was washed with water, dried(Na₂SO₄), and concentrated in a rotary evaporator. The product wasobtained as a white solid (M: 52 mg, yield: 68%).

C)(3-Methyl-3-naphthalen-2-ylmethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

In a manner similar to that of Example 6, by reacting3-Methyl-3-naphthalen-2-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid (0.225 mmol) previously obtained in Example 15(B), Piperidine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 tit, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.41 (s, H), 3.04 (d, 2H), 3.34 (br s, 2H), 3.68 (br s, 2H), 4.09 (d,1H), 4.60 (d, 1H), 6.74 (m, 2H), 6.88 (dd, 1H), 6.95 (d, 2H), 7.12 (dd,1H), 7.42-7.46 (m, 3H), 7.69-7.74 (m, 2H), 7.79 (dd, 1H).

Example 16[3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-yl]-piperidin-1-yl-methanone

A) 3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester

To a solution of 4-Iodo-3-(2-methyl-allyloxy)-benzoic acid methyl ester(65 mg, 0.2 mmol) in DMF (2 mL) were added Potassium carbonate (54 mg,0.39 mmol), Tetrabutylammonium chloride (54 mg, 0.2 mmol), Palladiumacetate (3.5 mg, 0.02 mmol) in DMF (5 mL) and 1-Penten-1-ylboronic acid,(26 mg, 0.23 mmol). The resulting mixture was stirred under microwaveirradiation (160° C., 15 min), cooled to room temperature, filtered oversilica, washed with water, dried over MgSO₄ and concentrated. Columnchromatography (silica gel, heptane/CH₂Cl₂: 4/6) afforded title compoundas a slightly colorless oil.

B) 3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid

A mixture of3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidmethyl ester (200 mg, 0.73 mmol), sodium hydroxide (200 mg, 5 mmol),ethanol (7 ml) and water (1 ml) in tetrahydrofuran (7 ml), was stirredfor 12 h at room temperature. The reaction medium was acidified byadding a 1.2 M hydrochloric acid solution and extracted with ethylacetate. The organic phase was washed with water, dried (Na₂SO₄), andconcentrated in a rotary evaporator. The product was obtained ascolorless oil which crystallized (M: 155 mg, 82%).

C)[3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-yl]-piperidin-1-yl-methanone

In a manner similar to that of Example 6, by reacting3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(0.225 mmol) previously obtained in Example 16(B), Piperidine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ0.86 (t, 3H), 1.23-1.40 (m, 5H), 1.95 (dd, 2H), 2.28 (d, 2H), 3.35 (brs, 2H), 3.34 (br s, 2H), 3.67 (br s, 2H), 4.13 (d, 1H), 4.40 (d, 1H),5.24-5.34 (m, 1H), 5.40-5.50 (m, 1H), 6.77 (d, 1H), 6.88 (dd, 1H), 7.06(d, 1H).

Example 173-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acidcyclohexylamide

In a manner similar to that of Example 6, by reacting3-((E)-Hex-2-enyl)-3-methyl-2,3-dihydro-benzofuran-6-carboxylic acid(0.225 mmol) previously obtained in Example 16(B), cyclohexylamine (0.25mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ0.86 (t, 3H), 1.19-2.03 (m, 13H), 2.28 (d, 2H), 3.89-4.02 (m, 1H), 4.14(d, 1H), 4.41 (d, 1H), 5.23-5.29 (m, 1H), 5.42-5.47 (m, 1H), 5.85 (d,1H), 7.09 (d, 1H), 7.11 (d, 1H), 7.27 (dd, 1H).

Example 183-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid cyclohexylamide

In a manner similar to that of Example 6, by reacting3-Methyl-3-naphthalen-1-ylmethyl-2,3-dihydro-benzofuran-6-carboxylicacid (0.225 mmol) previously obtained in Example 14(B), cyclohexylamine(0.25 mmol) in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil. NMR (CDCl₃): δ1.20-1.59 (m, 11H), 2.00 (d, 2H), 3.38 (dd, 2H), 3.90-3.98 (m, 1H), 4.09(d, 1H), 4.57 (d, 1H), 5.85 (d, 1H), 6.84 (d, 1H), 7.12-7.17 (m, 3H),7.33-7.46 (m, 3H), 7.75 (d, 1H), 7.82-7.87 (m, 2H).

Example 193-Benzyl-3-methyl-6-(piperidine-1-carbonyl)-1,3-dihydro-indol-2-one

A) 4-Iodo-3-(2-methyl-acryloylamino)-benzoic acid methyl ester

To a stirred suspension of Methyl 3-amino-4-iodobenzoate (1.67 g, 6mmol) and Methacrylic acid (568 mg, 6.6 mmol) in dichloromethane (60 mL)and DMF (60 mL) were addedO-(7-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HAM) (2.5 g, 6.6 mmol) and then a solution ofN,N-diisopropylethylamine (1.16 g, 1560 μL, 9 mmol) in DMF (20 mL). Thereaction mixture was stirred at ambient temperature for 24 h. Thereaction medium was acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase was washedwith water, dried (MgSO₄), and concentrated to give the amide which waspurified by flash chromatography (AcOEt/heptane: 5/5).

B) 3-Benzyl-3-methyl-2-oxo-2,3-dihydro-1H-indole-6-carboxylic acidmethyl ester

In a manner similar to that of Example 1B, by reacting4-Iodo-3-(2-methyl-acryloylamino)-benzoic acid methyl ester (1.37 mmol)obtained in Example 19(A), in DMF (20 mL), potassium carbonate (379 mg,2.74 mmol), tetrabutylammonium chloride (380 mg, 1.37 mmol), palladiumacetate (25.6 mg, 0.136 mmol) and Phenylboronic acid (200 mg, 1.64mmol), expected derivative was obtained as an colorless oil afterpurification by flash chromatography (AcOEt/heptane: 4/6).

C) 3-Benzyl-3-methyl-2-oxo-2,3-dihydro-1H-indole-6-carboxylic acid

In a manner similar to that of Example 1C, by reacting3-Benzyl-3-methyl-2-oxo-2,3-dihydro-1H-indole-6-carboxylic acid methylester (1.06 mmol) obtained in Example 19(B), sodium hydroxide (260 mg,6.5 mmol), ethanol (10 ml) and water (1 ml) in tetrahydrofuran (10 ml),expected derivative was obtained as a white solid.

D) 3-Benzyl-3-methyl-6-(piperidine-1-carbonyl)-1,3-dihydro-indol-2-one

In a manner similar to that of Example 6, by reacting3-Benzyl-3-methyl-2-oxo-2,3-dihydro-1H-indole-6-carboxylic acid (0.225mmol) previously obtained in Example 19(C), cyclohexylamine (0.25 mmol)in dichloromethane (2 mL) and DMF (1 mL),O-(7-Azabenzothiazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU) (94 mg, 0.25 mmol) and a solution ofN,N-diisopropylethylamine (44 mg, 59 μL, 0.34 mmol) in DMF (1 mL)expected derivative was obtained as an colorless oil after purificationby flash chromatography (AcOEt/heptane: 7/3).

Example 20(3-Benzyl-3-methoxymethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

A) [3-(2-Chloromethyl-allyloxy)-4-iodo-phenyl]-piperidin-1-yl-methanone

A mixture of Cesium carbonate (940 mg, 2.88 mmol),3-Hydroxy-4-iodo-benzoic acid methyl ester (400 mg, 1.44 mmol),3-Chloro-2-chloromethyl-1-propene (360 mg, 2.88 mmol) indimethylformamide 20 mL was stirred at room temperature for 48 h. Thereaction medium was acidified by adding a 1.2 M hydrochloric acidsolution and extracted with ethyl acetate. The organic phase was washedwith water, dried (Na₂SO₄), concentrated in a rotary evaporator andpurified by flash chromatography.

B) 1-(4-iodo-3-{[2-(methoxymethyl)prop-2-enyl]oxy}benzoyl)piperidine

To a solution of[3-(2-Chloromethyl-allyloxy)-4-iodo-phenyl]-piperidin-1-yl-methanone(200 mg, 0.48 mmol) in anhydrous methyl ethyl ketone (5.3 mL) was addedwith Sodium methylate, (124.46 mg, 0.56 mmol). The reaction mixture washeated at 70° C. for 4 h. Additional 0.1 mL of sodium methylate wasadded after heating the reaction at 80 C for 5 hours. Reaction was leftovernight at r.t. The mixture was diluted filtrated, washed with waterand dried over MgSO₄. Evaporation of the solvent and of the remainingbromopropene in vacuo afforded the requisite alkylated ester as a yellowoil. M: 210 mg, Yield: 100% raw. The desired compound was purified byflash chromatography (AcOEt/heptane: 4/6)

C)(3-Benzyl-3-methoxymethyl-2,3-dihydro-benzofuran-6-yl)-piperidin-1-yl-methanone

In a manner similar to that of Example 1(B), by reacting1-(4-iodo-3-{[2-(methoxymethyl)prop-2-enyl]oxy}benzoyl)piperidine (0.4mmol) obtained in Example 20(B), in DMF (6 mL), potassium carbonate (111mg, 0.8 mmol), tetrabutylammonium chloride (111 mg, 0.4 mmol), palladiumacetate (7 mg, 0.38 mmol) and Phenylboronic acid (60 mg, 0.5 mmol),expected derivative was obtained as an colorless oil after purificationby flash chromatography (AcOEt/heptane: 4/6).

Additional compounds of Formula I-V include:

Additional compounds of Formula VI include:

Biological Activity Assay CB1 Binding Assay

Cell membrane homogenates (25 μg protein) were incubated for 120 min at37° C. with 0.5 nM [³H]CP 55940 (the reference standard[Rinaldi-Carmona, 1996 #1320]) in the absence or presence of the testcompound in a buffer containing 50 mM Tris HCl (pH 7.4), 5 mM MgCl₂, 2.5mM EDTA, and 0.3% bovine serum albumin (BSA). Nonspecific binding wasdetermined in the presence of 10 μM WIN 55212-2. After being incubated,the samples were filtered rapidly under vacuum through glass fiberfilters (GF/B; Packard) presoaked with 0.3% PEI and rinsed several timeswith ice-cold buffer containing 50 mM Tris HCl (pH 7.4) and 0.5% BSAusing a 96-sample cell harvester (Unifilter; Packard). The filters weredried then counted for radioactivity in a scintillation counter(Topcount; Packard) using a scintillation cocktail (Microscint 0;Packard). The results were expressed as a percentage of the inhibitionof the control radioligand-specific binding. The reference standardcompounds were tested in each experiment at several concentrations toobtain a competition curve from which its IC₅₀ was calculated.

CB2 Binding Assay

Cell membrane homogenates (15 μg protein) were incubated for 120 mM at37° C. with 0.8 nM [3H]WIN 55212-2 (the reference standard [Munro, 1993#1321]) in the absence or presence of the test compound in a buffercontaining 50 mM HEPES/Tris HCL (pH 7.4), 5 mM MgCl2, 2.5 mM EGTA, and0.1% BSA. Nonspecific binding was determined in the presence of 10 μMWIN 55212-2. After being incubated, the samples were filtered rapidlyunder vacuum through glass fiber filters (GF/B; Packard) presoaked with0.3% PEI and rinsed several times with ice-cold buffer containing 50 mMTris HCl (pH 7.4) and 0.5% BSA using a 96-sample cell harvester(Unifilter; Packard). The filters were dried then counted forradioactivity in a scintillation counter (Topcount; Packard) using ascintillation cocktail (Microscint 0; Packard). The results wereexpressed as a percentage of the inhibition of the controlradioligand-specific binding. The reference standard compounds weretested in each experiment at several concentrations to obtain acompetition curve from which its IC₅₀ was calculated.

CB1/CB2 Functional Assay

A dose response curve was generated at eight concentrations in duplicateon CB1 and CB2 in light of reference agonists. The reference agonistsfor cannabinoid receptors was CP55,940. See FIGS. 1A, 1B, 2A, 2B, 3A and3B.

Membranes (CB1, ES-110-MG or CB2, ES-111-MG) were mixed with GDP(volume:volume) and incubated for at least 15 min on ice. In parallel,GTPγ[³⁵S] were mixed with the beads (volume:volume) just before startingthe reaction. The following reagents were successively added in thewells of an Optiplate: 50 μl of ligand, 20 μl of the membranes:GDP mix,10 μl of assay buffer for agonist testing and 20 μl of the GTPγ[³⁵S]:beads mix. The plates were covered with a topseal, shaken on an orbitalshaker for 2 min, and then incubated between 30 to 60 min. at roomtemperature. Then the plates were centrifuged for 10 min at 2000 rpm,incubated at room temperature between 1 to 4 hours and counted for 1 minwith a PerkinElmer TopCount reader.

Using the above-identified assays, the binding data for certainheterocyclic compounds to the CB1 and CB2 receptors have been obtainedand is provided in Tables 1, and Table2 below.

TABLE 1 CB1 - Binding Data % Inhibition of Test Example Control Specific% of Control Specific Binding SEM % Concentration No. Binding 1^(st)2^(nd) Mean Control (MD) 1 14 85.7 85.3 85.5 0.2 1.0E−05 2 68 29.9 33.831.8 2 1.0E−05 3 71 22 36 29 7 1.0E−05 4 9 85.9 95.1 90.5 4.6 1.0E−05 543 53.5 60.8 57.2 3.7 1.0E−05 6 26 66.8 80.4 73.6 6.8 1.1E−05

TABLE 2 CB2 - Binding Data % Inhibition of Test Example Control Specific% of Control Specific Binding SEM % Concentration No. Binding 1^(st)2^(nd) Mean Control (MD) 1 23 78.3 74.8 76.6 1.8 1.0E−05 2 85 21.3 8.614.9 6.4 1.0E−05 3 91 13 5.8 9.4 3.6 1.0E−05 4 15 83.9 85.5 84.7 0.81.0E−05 5 72 29.9 25.1 27.5 2.4 1.0E−05 6 31 71.6 67.3 69.4 2.2 1.0E−05

Using the above identified functional assay, the activity of the CB1 andCB2 receptors was obtained and is shown in Tables 3 and 4 below. Thisdata is also charted in FIGS. 1 through 3.

TABLE 3 CB1 Functional Activity Activty % Inhibition of EC50 (nM)Example Control Specific for GTP % Activation Compound No. Binding CB1Binding Average Function 2 68 0 −35.79 Inverse Agonist 3 71 0 22.85Agonist 5 43 0 −36.02 Inverse Agonist

TABLE 4 CB2 Functional Activity Data % Inhibition of EC50 (nM) ExampleControl Specific for GTP % Activation Compound No. Binding CB2 BindingAverage Function 2 85 478.69 52.94 Agonist 3 91 160.09 87.2 Agonist 5 72408.51 55.71 Agonist

In Vivo Testing I. Assessment of Mechanical Allodynia in Rats

All experiments were performed on male Sprague-Dawley rats (200-250 g).Rats were housed individually in plastic cages with soft bedding at roomtemperature and maintained on a 12-hour light-dark cycle with freeaccess to food and water.

Surgical Procedures

All surgical procedures were performed with the rats anesthetizedinhalational isoflurane in 100% oxygen, induced at 5% and maintained at2%. Animals that show neurologic deficits after surgery were excludedfrom the study. Prophylactic antibiotic (enrofloxacin 5 mg/kgsubcutaneously) and analgesic (buprenorphine, 0.2-0.5 mg/kg, ormorphine, 2.5 mg/kg, both given subcutaneously) were administered oncedaily for 3 days. Lumbar 5/6 Spinal-Nerve Ligation (Nerve-LigationModel)

Neuropathic pain was induced following the methods of Kim and Chung. KimS H, Chung J M. An experimental model for peripheral neuropathy producedby segmental spinal nerve ligation in the rat. Pain 1992; 50:355-63.Rats were anesthetized and placed prone under a microsurgical apparatus.A midline incision was made on the back, and the right paraspinalmuscles were separated from the spinous processes at the L4S2 levels.The L6 transverse process was carefully removed, and the L4/5 spinalnerves were identified. The L5 nerve was tightly ligated with a 6-0 silksuture. The right L6 spinal nerve was then located just caudal andmedial to the sacroiliac junction and tightly ligated with a silksuture.

Intrathecal Catheterization

Two weeks later after spinal nerve ligation, Intrathecal catheters(PE-10 tubing) was inserted into the rats while they were anesthetizedwith isoflurane, as described by Yaksh and Rudy. Yaksh T L, Rudy T A.Chronic catheterization of the spinal subarachnoid space. Physiology &Behavior 1976; 17:1031-6. A midline incision was made on the back of theneck. The muscle was freed at the attachment to the skull exposing thecisternal membrane. The membrane was opened with a stab blade and an 8.5cm polyethylene (PE-10) catheter was then inserted through the cisternalopening, and passed carefully and caudally into the intrathecal space atthe L1-L3 spinal segments. The end of the catheter was tunneled throughthe subcutaneous space over the frontal bones, flushed with 10 μlsaline, and then plugged with a short length of wire. Animal testing wasperformed 5-7 days after intrathecal catheter placement.

Results

To assess mechanical allodynia, the mechanical paw withdrawal thresholdwas measured with a series of von Frey hairs (range 0.4-15 g). Rats wereplaced in elevated Perspex enclosures (28 cm×15 cm×18 cm) with wire meshbases and given 15-20 min to acclimatize to the testing environment.Rats will be allowed to acclimatize for 30 min in a clear plastic cagewith a wire mesh bottom. The calibrated von Frey filament fibers wereapplied to the hindpaw briefly for 6 seconds to determine the pawwithdrawal threshold before and after drug injection (intraperitoneallyor intrathecally). A series of von Frey filaments with exponentiallyincremental stiffness (0.4, 0.7, 1.2, 2.0, 3.6, 5.5, 8.5 and 15 g) wereused to measure the 50% threshold for hindpaw withdrawal in awake,unrestrained rats. Chaplan S R, Bach F W, Pogrel J W, Chung J M, Yaksh TL. Quantitative assessment of tactile allodynia in the rat paw. Journalof Neuroscience Methods 1994; 53:55-63. Brisk paw withdrawal from thepressure of a filament gently bent against the plantar paw was definedas a positive response, and absence of withdrawal within 6 s as anegative response. Filaments were touched to the hindpaw in sequentialascending or descending order until the threshold of response is crossed(allowing about 10 s between each increment of the von Frey filaments).Each time the threshold is crossed, the direction of stimuluspresentation was reversed and the procedure will be resumed. Fourresponses were collected after the first threshold detection, and the50% withdrawal thresholds were interpolated. In cases where responsethresholds fell outside the range of detection, 15.00 and 0.25 g were,respectively, assigned for continuous negative or positive responses tothe limit of stimuli.

Drugs

The compound of Example 3 was prepared in dimethyl sulfoxide (DMSO).

Results

IP administration of 30 mg/kg in 0.5 ml of the compound of Example 3 asshown in FIG. 4 produced an increase in mechanical paw withdrawalthreshold. The peak effect for both drugs was noted within 5 minfollowing IP administration. The high threshold (15 g) was maintainedbeyond the 2-h observation period for the compound of Example 3.

IT administration of the compound of Example 3 as shown in FIG. 5produced an increase in mechanical paw withdrawal threshold that lastedfor the 90-min observation period. No behavioral abnormalities or sideeffects were noted in animals.

Intraperitoneal (IP) administration of the compound of Example 3compared to morphine is shown in FIG. 6.

Conclusions

The compound of Example 3 is a very potent analgesic in the neuropathicpain animal model when administered IP. The compound of Example 3appears to be a longer-acting compound.

II. In Vitro Receptor Radioligand Binding Studies

AM630 and AM251 were purchased from Tocris Bioscience (Ellisville,Mich., USA). AM1241 and naloxone were purchased from Sigma-Aldrich Corp.(St. Louis, Mo., USA). WIN 55, 212-2, AM1241, paclitaxel, and allchemicals used for synthesis of the compound of Example 3 were purchasedfrom Sigma-Aldrich, St. Louis, Mo.

The compound of Example 3 was synthesized as shown in FIG. 7. Briefly,the 3-hydroxy-4-iodo-benzoic acid was obtained by iodination (NaI,NaOCl, NaOH, MeOH, 80% yield) of meta-hydroxybenzoic acid. Thecorresponding methyl benzoate was obtained by esterification (MeOH,H₂SO₄). The phenol derivative was then coupled with3-bromo-2-methyl-propene using potassium carbonate in methylethylketonein 98% yield. The resulting compound was submitted to a Pd-catalyzedtandem cyclization/Suzuki-coupling reaction to afford the correspondingheterocyclic in 95% yield. Szlosek-Pinaud, M., et al., EfficientSynthetic Approach to Heterocycles Possessing the3,3-Disubstituted-2,3-Dihydrobenzofuran Skeleton Via DiversePalladium-Catalyzed Tandem Reactions, Tetrahedron, 2007, 63:3340-9. Thecompound of Exhibit 3 was obtained after saponification (97% yield) andcoupling with piperidine (71% yield).

Analytical Data for the Compound of Example 3

1-[(3-benzyl-3-methyl-2,3-dihydro-1-benzofuran-6-yl)carbonyl]piperidine,¹H NMR (CDCl₃): δ 1.37 (s, 3H), 1.58-1.69 (m, 6H), 2.8 (d, J=13.5 Hz,1H), 2.90 (d, J=13.5 Hz, 1H), 3.34 (br s, 2H), 3.68 (br s, 2H), 4.09 (d,J=8.7 Hz, 1H), 4.53 (d, J=8.7 Hz, 1H), 6.75 (d, J=1.2 Hz, 1H), 6.88 (dd,J=1.2 Hz, J=7.5 Hz) 6.94 (d, J=7.5 Hz, 1H), 6.99-7.02 (m, 2H), 7.22-7.24(m, 3H). ¹³C NMR (CDCl₃): δ 24.56 (CH₃), 24.64 (CH₂), 25.67 (CH₂), 26.56(CH₂), 43.15 (CH₂), 46.22 (C), 46.57 (CH₂), 48.75 (CH₂), 82.28 (CH₂),108.20 (CH), 119.09 (CH), 123.43 (CH), 126.58 (CH), 127.99 (CH), 130.36(CH), 136.21 (C), 136.75 (C), 137.26 (C), 159.47 (C), 170.19 (C═O). HRMS(ES+) calcd for C₂₂H₂₅NO₂ (M+H⁺), m/e, 336.1964; found, 336.1958.

The compound of Example 3 was screened in a competitive bindingexperiment using membranes of Chinese hamster ovarian cells (CHO-K1)expressing selectively the human CB1 receptor, at differentconcentrations, in duplicate. Mukherjee, S., et al., Species Comparisonand Pharmacological Characterization of Rat and Human CB2 CannabinoidReceptors, Eur J Pharmacol, 2004, 505:1-9. The competition bindingexperiment was performed in 96 well plates (Masterblock®, Cataloguenumber 786201, Greiner Bio-One) containing binding buffer (50 mM Tris pH7.4, 2.5 mM EDTA, 0.5% protease free BSA, saponine 10 μg/ml),recombinant membrane extracts (2 μg protein/well) and 1 nM [³H]SR141716A (GE Healthcare, TRK1028, 42 Ci/mmol, diluted in bindingbuffer). Non-specific binding is determined in the presence of 10 μMCP55,940 (Tocris, Bioscience, Ellisville, Mich., USA). The sample isincubated in a final volume of 0.1 ml for 60 min at 25° C. and thenfiltered on GF/C Unifilter microplate (Perkin Elmer, Catalogue number6005177) presoaked in 0.05% Brij for 2 hrs at room temperature. Filtersare washed six times with 4 ml of cold binding buffer and bound [³H]SR141716A is determined by liquid scintillation counting. IC₅₀ weredetermined by non-linear regression using one site competition equation.The inhibition constants (Ki) were calculated using the Cheng Prusoffequation (Ki=IC₅₀/(1+(L/K_(D))), where L=concentration of radioligand inthe assay, and K_(D)=affinity of the radioligand for the receptor).

The compound of Example 3 was screened in a competitive bindingexperiment using membranes of Chinese hamster ovarian cells (CHO-K1)expressing selectively the human CB2 receptor, at differentconcentrations, in duplicate. Mukherjee, S., et al., Species Comparisonand Pharmacological Characterization of Rat and Human CB2 CannabinoidReceptors, Eur J Pharmacol, 2004, 505:1-9. The competition bindingexperiment was performed in 96 well plates (Masterblock®, Cataloguenumber 786201, Greiner Bio-One) containing binding buffer (50 mM Tris pH7.4, 2.5 mM EDTA, 0.5% protease free BSA), recombinant membrane extracts(0.25 μg protein/well) and 1 nM [³H]CP 55,940 (Perkin Elmer, NEX-1051,161 Ci/mmol, diluted in binding buffer). Non-specific binding isdetermined in the presence of 10 μM CP55940 (Tocris, Bioscience,Ellisville, Mich., USA). The sample is incubated in a final volume of0.1 ml for 60 min at 30° C. and then filtered on GF/B Unifiltermicroplate (Perkin Elmer, Catalogue number 6005177) presoaked in 0.5%PEI for 2 hrs at room temperature. Filters are washed six times with 4ml of cold buffer (50 mM Tris pH 7.4, 2.5 mM EDTA, 0.5% protease freeBSA) and bound [³H]CP55940 is determined by liquid scintillationcounting. IC₅₀ were determined by non-linear regression using one sitecompetition equation. The inhibition constants (Ki) were calculatedusing the Cheng Prusoff equation (Ki=IC₅₀/(1+(L/K_(D))), whereL=concentration of radioligand in the assay, and K_(D)=affinity of theradioligand for the receptor). GTPγ[³⁵S] Functional Assays

Functional activity was evaluated using GTPγ[³⁵S] assay in CHO membraneextracts expressing recombinant hCB1 (human CB1) receptors or hCB2(human CB2) receptors. The assay relies on the binding of GTPγ[³⁵S], aradiolabeled nonhydrolyzable GTP analogue, to the G protein upon bindingof an agonist of the G-protein-coupled receptor. In this system,agonists stimulate GTPγ[³⁵S] binding whereas neutral antagonist have noeffect and inverse agonists decrease GTPγ[³⁵S] basal binding.

The compound of Example 3 was solubilized in 100% DMSO at aconcentration of 10 mM within 4 hours of the first testing session(master solution). A predilution for the dose response curve wasperformed in 100% DMSO and then diluted 100 fold in assay buffer at aconcentration 2 fold higher than the concentration to be tested. Thecompound of Example 3 was tested for agonist and antagonist activitiesat eight concentrations in duplicate: 10, 3, 1, 0.3, 0.1, 0.03, 0.01 and0.001 μM with CP55,940 (Tocris, Bioscience, Ellisville, Mich., USA) asreference agonist. For GTPγS membranes were mixed with GDP diluted inassay buffer to give 30 μM solution (volume:volume) and incubated for atleast 15 min on ice. In parallel, GTPγ[³⁵S] (GE Healthcare, Cataloguenumber SJ1308) were mixed with the beads (PVT-WGA (GE Healthcare,RPNQ001)), diluted in assay buffer at 50 mg/ml (0.5 mg/10 μl)(volume:volume) just before starting the reaction. The followingreagents were successively added in the wells of an Optiplate (PerkinElmer): 50 μL of ligand or the reference antagonist (AM251), 20 μl ofthe membranes:GDP mix, 10 μL of reference agonist (CP55,940) athistorical EC₈₀ (30 nM), and 20 μl of the GTPγ[³⁵S]:beads mix. Theplates were covered with a topseal, shacked on an orbital shaker for 2min, and then incubated for 1 hour at room temperature. Then the plateswere centrifuged for 10 min at 2000 rpm and counted for 1 min/well witha PerkinElmer TopCount reader. Assay reproducibility was monitored bythe use of reference compound CP55,940. For replicate determinations,the maximum variability tolerated in the test was of ±20% around theaverage of the replicates. Efficacies (E_(max)) for CB1 or CB2 areexpressed as a percentage relative to the efficacy of CP55,940.

cAMP Activation Assays

The compound of Example 3 was tested for agonist activity at the rat CB1(rCB1) and rCB2 receptors, at eight concentrations, in duplicate: 10, 3,1, 0.3, 0.1, 0.03, 0.01 and 0.001 μM. Recombinant cells grown to mid-logphase in culture media without antibiotics were detached with PBScontaining 5 mM EDTA, centrifuged and resuspended in assay buffer at aconcentration of 16.6×105 cells/ml. The test was performed in 96 wellplates. For testing, 12 μl of cells (2×10³ cells/well) were mixed with12 μl of agonist at increasing concentrations. After incubation for 10min at room temperature, 6 μl of the reference agonist (CP55,940) wereadded at a final agonist concentration corresponding to the historicalEC₈₀. The plates were then incubated for 30 min at room temperature.After addition of the lysis buffer, cAMP concentrations were estimated,according to the manufacturer specification, with the HTRF kit fromCis-Bio International (Catalogue number 62AM2PEB).

In Vivo Biological Activity Studies

Adult, male Sprague Dawley (Harlan Sprague Dawley, Indianapolis, Ind.)rats weighing 120-150 gm were used in experimental procedures approvedby the Animal Care and Use Committee of the M. D. Anderson CancerCenter, University of Texas. Animals were housed three per cage on a12/12 hr light/dark cycle with water and food pellets available adlibitum.

Lumbar 5/6 Spinal Nerve Ligation Pain Model

All surgical procedures were performed under deep isoflurane anesthesiain 100% O2. The spinal nerve ligation (SNL) was performed as describedpreviously. Kim, S. H., et al., An Experimental Model for PeripheralNeuropathy Produced by Segmental Spinal Nerve Ligation in the Rat, Pain,1992, 50:355-63. Briefly, a midline incision above the lumbar spineexposed the left L6 transverse process. The process was then removed,the left L5 and L6 spinal nerves were isolated, and both nerves weretightly ligated with 6-0 silk. Prophylactic antibiotic (norfloxacin 5mg/kg subcutaneously) and analgesic (buprenorphine, 0.2-0.5 mg/kg, ormorphine, 2.5 mg/kg, given subcutaneously) were administered once dailyfor 3 days. All the experiments were conducted 10-14 days after spinalnerve ligation.

Paclitaxel-Induced Neuropathy Model

Groups of rats received daily i.p. injections of either vehicle or 1.0mg/kg paclitaxel daily for four consecutive days for a final cumulativedose of 4 mg/kg; using an injection volume of 1 ml/kg. Polomano, R. C.,et al., A Painful Peripheral Neuropathy in the Rat Produced by theChemotherapeutic Drug, Paclitaxel, Pain, 2001, 94:293-304. The vehicleused in our experiments was the same vehicle used clinically forpaclitaxel injections and is composed of a mixture of 10% saline andCremophor EL® and ethylene oxide. Baseline responses to mechanicalstimulation of the hindpaw (see below) were established on day zero andcontinued daily until the development of neuropathy was confirmed.

Assessment of Mechanical Withdrawal Thresholds

Rats were placed in a compartment with a wire mesh bottom and allowed toacclimate for a minimum of 30 min before testing. Mechanical sensitivitywas assessed using a series of Von Frey filaments with logarithmicincremental stiffness (0.41, 0.70, 1.20, 2.00, 3.63, 5.50, 8.50, and15.1 g) (Stoelting, Wood Dale, Ill.) as previously described, and 50%probability withdrawal thresholds were calculated with the up-downmethod. Chaplan, S. R., et al., Quantitative Assessment of TactileAllodynia in the Rat Paw, J. Neurosci. Methods, 1994, 53:55-63; Dixon,W., The Up-and-Down Method for Small Samples, J. Am. Stat. Assoc., 1965,60:967-78. In brief, beginning with the 2.0-g probe, filaments wereapplied to the plantar surface of a hind paw for 6-8 s, in an ascendingor descending order after a negative or positive withdrawal response,respectively. Six consecutive responses from the first change in theresponse were used to calculate the withdrawal threshold (in grams). Incases where response thresholds fell outside the range of detection,15.00 and 0.25 g were, respectively, assigned for continuous negative orpositive responses to the limit of stimuli. The percent maximal possibleeffect (% MPE) was calculated as ([postdrug threshold−baselinethreshold]/[cutoff threshold (15 g)−baseline threshold])×100.

Assessment of Thermal Paw Withdrawal Latencies

To determine sensitivity to noxious heat, rats were placed in plexiglasenclosures on a transparent glass surface maintained at 30° C. andallowed to acclimate for 30 min. A thermal testing apparatus, consistingof a heat-emitting projector lamp and an electronic timer, was used. Thedevice was activated after the lamp is placed directly beneath theplanter surface of the hindpaw. The paw withdrawal latency in responseto the radiant heat was recorded by a digital timer. A cutoff of 30 swas used to prevent potential tissue damage. After the baseline wasmeasured, three groups of naïve rats (n=10) received 1.0, 3.0, or 10mg/kg of the compound of Example 3i.p. Response latencies weredetermined twice for each rat before drug injection and at 5, 10, 15,30, 45, 60, 90 and 120 min after IP injection. The percent maximalpossible effect (% MPE) was calculated as ([postdrug latency−baselinelatency]/[cutoff time (30 s)−baseline latency])×100.

Open Field Chamber Testing

The automated open-field chamber (Med Associates ENV-515 TestEnvironment, St. Albans, Vt.) 43.2×43.2×30.5 cm (L×W×H) equipped withthree pairs of 16 infrared arrays that continually monitored theanimal's movement was used to determine potential CNS effects of thecompound of Example 3, WIN55212-2, and haloperidol in naïve rats. Ratswere individually tested 15 min after i.p. drug administration. Theinfrared beams were set 2.5 cm apart horizontally and at a height of 3cm above the floor, with the rearing array set at 12 cm from the floor.The area in the box was divided into 4 equal quadrants (zones), withdata collected within each quadrant and across quadrants (zone entries).An ambulatory movement was defined as a motion of at least 5 cm and wascoded by quadrant. Vertical movements were counted when the rat movedvertically a minimum of 12 cm from the floor. Zone entries were definedas an entry into a zone (from another zone). Entry into a zone wascounted when the rat was far enough into the zone to break 2 sets ofphotoelectric beams for the new zone beams during an ambulatorymovement.

Data Analysis

Statistical analyses were carried out using BMDP 2007 (StatisticalSolutions, Saugus, Mass., USA) and Graph Pad Prism (version 4.03; GraphPad Software Inc., San Diego, Calif., USA). Data were analyzed usingone-way ANOVA, repeated measures ANOVA, or t-test where appropriate. IfANVOA was significant, Tukey-Kramer post hoc analysis was used formultiple group comparison. Area under the curve (AUC) was calculatedusing the trapezoidal rule. The results are presented as mean±s.e. meanand were considered significant at P<0.05. Analyses of the dose-responsecurves and statistics were obtained using the pharmacologic softwareprograms of Tallarida and Murray and included calculation of the ED₅₀values and their 95% confidence intervals (CI). Tallarida, R. J., etal., Manual of Pharmacologic Calculations With Computer Programs, Seconded. New York: Springer-Verlag, 1987.

Results In Vitro Characterization of the Compound of Example 3

In the competition binding assays performed in membranes of CHOexpressing selectively the hCB2 receptor, the compound of Example 3displaced [³H]CP55,490 from human receptors with Ki values of 422±123nM. The compound of Example 3 did not demonstrate detectable radioactiveligand displacement at hCB1 receptors (up to 10 μM). See Table 5immediately below.

TABLE 5 Radioligand Competition Binding Assays Mean Ki (nM) Ligands hCB1hCB2 Compound of >10,000 422 ± 123 Example 3 CP55,940 3.4 1.8 ± 1.1

The EC₅₀ value of the compound of Example 3 in GTPγ[³⁵S] functionalassays was 128±32 nM at hCB2 with an Emax of 88%. The compound ofExample 3 did not result in any agonistic or antagonistic activities athCB1 receptors. In cAMP activation assays, the compound of Example 3 hadan EC₅₀ of 21.7±7.9 nM at rCB2 receptors. The compound of Example 3 didnot exhibit any activity at rCB1 receptors. See Table 6 immediatelybelow.

TABLE 6 GTPγ[³⁵S] Functional and cAMP Activation Assays Agonist EC₅₀(mean ± s.e. mean) relative to CP55,490 (%) GTPγ[³⁵S] cAMP functionalassays activation assays Ligands hCB1 hCB2 rCB1 rCB2 Compound of >10,000128 ± 32  >10,000 21.7 ± 7.9  Example 3 CP55,940 9 ± 1.3 6.5 ± 2.1 0.14± 0.1 1.13 ± 0.13Effects of the Compound of Example 3 in Naïve Rats

Administration of 1 mg/kg or 3 mg/kg of the compound of Example 3i.p.did not block the nociceptive effect of a thermal stimulus applied tohind paws of naïve rats. Increasing the dose of the compound of Example3 to 10 mg/kg i.p. resulted in a short-lasting antinociceptive effect(FIG. 9).

Effects of the Compound of Example 3 on Tactile Allodynia in a SNLNeuropathic Pain Model

In rats, SNL produced tactile allodynia one week following surgery asdemonstrated by a reduction in paw withdrawal threshold to mechanicalstimulation to 2.5±0.19 g using Von Frey filaments (FIG. 10A). Thecompound of Example 3 treatment attenuated tactile allodynia in adose-related manner with an ED₅₀ of 7.48 mg/kg i.p. (95% CI=5.6-9.9mg/kg). The higher doses (10 mg/kg and 15 mg/kg) produced significantlyantiallodynic effect than that noted with 5 mg/kg of the compound ofExample 3 (FIG. 11A, 11B & 11C).

The receptor specificity of the compound of Example 3 was investigatedin SNL model using receptor-selective antagonists (FIG. 12).Pretreatment with AM630 (5 mg/kg i.p.), a CB2 receptor-selectiveantagonist, significantly reversed antiallodynic effects induced by i.p.administration of 10 mg/kg the compound of Example 3 (P<0.001).Hosohata, Y., et al., AM630 Antagonism of Cannabinoid-Stimulated [ ³⁵S]GTP Gamma S Binding in the Mouse Brain, Eur. J. Pharmacol, 1997,321:R1-3; Ross, R. A., et al., Agonist-Inverse Agonist Characterizationat CB1 and CB2 Cannabinoid Receptors of L759633, L759656, and AM630, Br.J. Pharmacol., 1999, 126:665-72. In contrast, pretreatment with AM251 (5mg/kg i.p.), a selective CB1 receptor antagonist, had no effect on theantiallodynic effects induced by the compound of Example 3. Gatley, S.J., et al., 123I-labeled AM251: A Radioiodinated Ligand Which Binds InVivo to Mouse Brain Cannabinoid CB1 Receptors, Eur J Pharmacol, 1996,307:331-8. The rats treated with CB1 or CB2 receptor antagonists aloneat the doses used in the present studies did not exhibit any change inpaw withdrawal threshold as compared with the vehicle-treated animals(FIG. 12).

I.p. administration of 15 mg/kg AM1241, a CB2 ligand producedantiallodynic effects that was significantly different (P<0.001) fromthe vehicle (FIG. 13). Ibrahim, M. M., Activation of CB2 CannabinoidReceptors by AM1241 Inhibits Experimental Neuropathic Pain: PainInhibition by Receptors Not Present in the CNS, Proc. Natl. Acad. Sci.U.S.A., 2003, 100:10529-33. However, the antiallodynic effects of 10mg/kg the compound of Example 3i.p. was significantly (P<0.001) greaterthan that observed with 15 mg/kg AM1241 i.p. The antinociceptive effectsAM1241 have been shown to be dependent on β-endorphin and μ-opioidreceptor system and were blocked by the administration of naloxone orantiserum to β-endorphin. Ibrahim, M. M., et al., CB2 CannabinoidReceptor Activation Produces Antinociception by Stimulating PeripheralRelease of Endogenous Opioids, Proc. Natl. Acad. Sci. U.S.A., 2005,102:3093-8. To investigate whether the antiallodynic effects of thecompound of Example 3 are mediated via μ-opioid receptor-dependentactivity, SNL rats were injected with the opioid receptor antagonistnaloxone (10 mg/kg i.p.) 15 min prior to the administration of thecompound of Example 3. Naloxone pretreatment had no effect on theantiallodynic activity of the compound of Example 3 (FIG. 13, P<0.001).However, under similar conditions, pretreatment with naloxonesignificantly reversed the analgesic effects induced by AM1241 at 15mg/kg i.p. (FIG. 13, P<0.01).

Prevention of Chemotherapy-induced Peripheral Neuropathy by CannabinoidReceptor Subtype 2 (CB2) Modulators

CB2 agonist is able to suppress neuropathic nociception induced by achemotherapeutic agent. Prevention of the development of this peripheralneuropathy by pre or co-administration of a CB2 modulator (or any otherdrug) with a chemotherapeutic agent is provided herein.

Paclitaxel is an antineoplastic drug used in cancer chemotherapy.Paclitaxel is used to treat patients with lung, ovarian, breast, headand neck cancer, and advanced forms of Kaposi's sarcoma. Neuropathicpain is one of the side effects associated with the use of paclitaxel.Mielke, S., et al., Peripheral neuropathy: a persisting challenge inpaclitaxel-based regimes, Eur J Cancer, 2006, 42:24-30. Neuropathicpain, a debilitating condition characterized by severe, persistent painthat is refractory to traditional analgesia. This side effect is alsoassociated with the use of other antineoplastic agents such as vincaalkaloids (e.g. vincristine), other taxane derivatives orplatinum-derivatives (e.g. cisplatin). In the US, the annual healthcarecost attributable to neuropathic pain is almost $40 billion. Turk, D.C.,Clinical effectiveness and cost-effectiveness of treatments for patientswith chronic pain, Clin J Pain, 2002, 18:355-65. There is no effectiveor satisfactory treatment for neuropathic pain. Warms, C. A., et al.,Treatments for chronic pain associated with spinal cord injuries: manyare tried, few are helpful, Clin J Pain, 2002, 18:154-63.

Chemotherapy-induced neuropathic pain is dose dependent; the mechanismof which might be accompanied by morphological to primary afferent.Recently, CB2 has emerged as a new target for the treatment ofneuropathic pain with an added advantage of lacking the psychotropicside effects that are normally seen with the use of the CB1 agonists.Cox, M. L., The antinociceptive effect of [Delta]9-tetrahydrocannabinolin the arthritic rat involves the CB2 cannabinoid receptor, EuropeanJournal of Pharmacology, 2007, 570:50-56; Beltramo, M., et al., C2receptor-mediated antihyperalgesia: possible direct involvement ofneural mechanisms, Eur J Neurosci, 2006, 23:1530-8; Ibrahim, M. M., CB2cannabinoid receptor mediation of antinociception, Pain, 2006,122:36-42; Guindon, J., et al., Cannabinoid CB2 receptors: a therapeutictarget for the treatment of inflammatory and neuropathic pain, Br JPharmacol, 2007.

Peripheral nerve injury induces CB2 protein expression in rat sensoryneurons. Wotherspoon, G., Peripheral nerve injury induces cannabinoidreceptor 2 protein expression in rat sensory neurons, Neuroscience,2005, 135:235-45. CB2 mRNA is expressed in dorsal root ganglia (DRG) ofneuropathic rats and is up-regulated in the spinal cord of neuropathicrats. CB2 mRNA expression was also shown in cultured spinal cordmicroglia and are upregulated in reactive microglia. Beltramo, M., CB2receptor-mediated antihyperalgesia: possible direct involvement ofneutral mechanicms, Eur J Neurosci, 2006, 23:1530-8; Ashton, J. C.,Class M: The Cannabinoid CB2 Receptor as a Target forInflammation-Dependent Neurodegeneration, Current Neuropharmacology,2007, 5:73-80; Romero-Sandoval, A., et al., Spinal Cannabinoid ReceptorType 2 Activation Reduces Hypersensitivity and Spinal Cord GlialActivation after Paw Incision, Anesthesiology, 2007, 106:787-794.

CB2 agonists are neuroprotective and are emerging as a target fortreating demyelinating diseases such as multiple sclerosis.Arevalo-Martin, A., et al., CB(2) cannabinoid receptors as an emergingtarget for demyelinating diseases: from neuroimmune interactions to cellreplacement strategies, Br J Pharmacol, 2007. For instance, treatmentwith a selective CB2 agonist JWH-015 not only switched microglial cellsmorphology toward normal in the spinal cord of Theiler's murineencephalomyelitis virus-infected mice, but also significantly improvedthe neurological recovery and remyelination process. Arevalo-Martin, A.,et al., Therapeutic action of cannabinoids in a murine model of multiplesclerosis, J Neurosci 2003, 23:2511-6. Cannabinoids abrogated majorhistocompatibility complex class II antigen expression, and decreasedthe number of CD4-infiltrating T cells. This protective mechanism of CB2agonists has been attributed to reduction in the release of inflammatorycytokines or reactive oxygen species and/or increase in the productionof protective molecules such as TGFa or anti-inflammatory cytokines suchas IL-10. Sagrego, O., et al., Cannabinoids and neuroprotection in basalganglia disorders, Mol Neurobiol, 2007, 36:82-91.

The use of CB2 agonists produce a dose-dependent reduction inmechano-allodynia and mechano-hyperalgesia in paclitaxel-treated rats,and the duration of effect is dependent on the duration of action of theCB2 agonist studied. There is evidence that a non-specific cannabinoidagonist with both CB1 and CB2 activities was able to prevent mechanicalallodynia induced by cisplatinum. Vera, G., et al., WIN 55, 212-2prevents mechanical allodynia but not alterations in feeding behaviourinduced by chronic cisplatin in the rat, Life Sci, 2007, 81:468-79.Provided herein is a treatment that prevents the development ofchemotherapy induced-peripheral neuropathy. Administration of thecompound of Example 3, a novel CB2 selective agonist, prevented thedevelopment of neuropathic pain induced by paclitaxel.

(A) Paclitaxel-Induced Neuropathy

First, an experiment was performed to demonstrate that paclitaxel canproduce the rat model of paclitaxel-induced neuropathy. A mixture ofsaline and CREMOPHOR® ELP 10% was used as vehicle for paclitaxel. It wasinjected at a concentration of 1.0 mg/kg intraperitoneally to thechemotherapy-treated group of rats on 4 consecutive days for a finalcumulative dose of 4 mg/kg to 18 rats.

Assessment of neuropathic pain. Paw withdrawal thresholds weredetermined daily in both hind paws of each animal using calibrated vonFrey monofilaments according to an up-down procedure. A series of vonFrey filaments with exponentially incremental degrees of stiffness (0.4,0.7, 1.2, 2.0, 3.6, 5.5, 8.5, and 15.1 g) was used to measure the 50%threshold for both hindpaw withdrawal in awake, unrestrained rats.Chaplan, S.R., Quantitative assessment of tactile allodynia in the ratpaw, Journal of Neuroscience Methods, 1994, 53:55-63. Brisk pawwithdrawal from the pressure of a filament gently bent against theplantar surface of the paw was defined as a positive response, andabsence of withdrawal within 6 sec was considered a negative response.The series of filaments touched the hindpaw in sequential ascending ordescending order of stiffness until the threshold of response wascrossed (allowing about 10 sec between each increment). Each time thethreshold was crossed, the direction of stimulus presentation wasreversed and the procedure resumed. Four responses were collected afterthe first threshold detection, and the 50% withdrawal thresholds wasinterpolated. In cases in which the response thresholds fall outside therange of detection, 15.1 and 0.25 g were assigned for continuousnegative or positive responses, respectively, to the limits ofstimulation. FIG. 17 and FIG. 18 show results from these experiments andthat peripheral neuropathy started to develop within a few days. FIG. 18reflects that a plateau was reached by the 10th day.

B) Prevention of Neuropathy Induced by Paclitaxel

These experiments were designed to show that the administration of thecompound of Example 3, 30 minutes prior to the administration ofpaclitaxel will prevent the development of neuropathy. Group 1 of ratsreceived paclitaxel for four days, as described immediately above insubpart (A) titled “Paclitaxel-induced Neuropathy.” In group 2, a doseof 15 mg/kg of the compound of Example 3, injected intraperitoneally wasadministered 30 minutes prior to the administration of paclitaxel. Ingroup 3, vehicle of the compound of Example 3 was administered 30 minprior to the administration of paclitaxel. Paw withdrawal thresholdswere determined daily in both hind paws of each animal using calibratedvon Frey monofilaments according to an up-down procedure as describedimmediately above in subpart (A) titled “Paclitaxel-induced Neuropathy.”The results are shown in FIG. 17.

FIGS. 19A and 19B show results from an experiment in which three groupsof rats were administered 0.25 mL of the compound of Example 3 or thevehicle, a mixture of NMP, propylene glycol, chromophore ELP(25%,25%,10%) in sterile water 30 min prior to the administration ofpaclitaxel. Two of the three experimental groups continued to receiveeither the vehicle or the compound of Example 3 daily for 11 more days.Paw withdrawal thresholds were determined daily in both hind paws ofeach animal using calibrated von Frey monofilaments according to anup-down procedure as described immediately above in subpart (A) titled“Paclitaxel-induced Neuropathy.” A fourth group of rats receivedpaclitaxel for four days, as described immediately above in subpart (A)titled “Paclitaxel-induced Neuropathy.” As shown in FIGS. 19A and 19B,continued administration of 15 mg/kg the compound of Example 3intraperitoneally (IP) daily completely prevented the development ofpaclitaxel-evoked mechano-allodynia. Administration of 15 mg/kg of thecompound of Example 3 for 4 days only did not prevent but significantlyprevented the severity of paclitaxel-evoked mechano-allodynia.

Effects of the Compound of Example 3 on Tactile Allodynia in aPaclitaxel-Induced Neuropathic Pain Model

Tactile allodynia was developed in 100% of rats 10 days after the startof paclitaxel administration as demonstrated by a reduction in pawwithdrawal threshold to mechanical stimulation to 2.9±0.19 g and2.8±0.15 g for the right and left paws, respectively using Von Freyfilaments (FIG. 10B). The compound of Example 3 suppressedpaclitaxel-evoked thermal hyperalgesia (FIGS. 14A and 14B) andmechanical allodynia (FIGS. 14C and 14D) relative to treatment withvehicle in a dose-dependent manner. This suppression was maximal at 20min. The calculated ED₅₀ of the compound of Example 3 for suppressingthermal hyperalgesia at 20 min was 13.5 mg/kg i.p. (95% CI=8.2-22 mg/kg)(FIG. 14B). Pretreatment with AM630 (5 mg/kg i.p.) significantlyreversed anti-hyperalgesic effects induced by i.p. administration of 15mg/kg the compound of Example 3 administered 15 min later (P<0.001)(FIG. 14A). The effect of 5 mg/kg AM1241 i.p. on reversing thermalhyperalgesia was significantly less than (P<0.05) that noted for 15mg/kg the compound of Example 3i.p. (FIG. 14A). The compound of Example3 dose-dependently attenuated tactile allodynia in this model, which isseen as an increase in the % MPE withdrawal threshold AUC (FIG. 14C)with an ED₅₀ of 24 mg/kg i.p. (FIG. 14D).

Administration of the Compound of Example 3 Prevents the Development ofNeuropathy Associated With Paclitaxel Administration

Administration of the compound of Example 3 with the start of paclitaxeladministration for 14 days [4 days concomitant with the administrationof paclitaxel and continued for further 10 days] resulted in preventionof paclitaxel-induced neuropathy in 100% of rats (FIG. 15).Administration of the compound of Example 3 for four days only resultedin short-lived prevention of paclitaxel-induced neuropathy. Melatonindid not provide any protection against neuropathy in this model.

Open Field Chamber Testing

In contrast to the compound of Example 3 (15 mg/kg i.p.), administrationof 7 mg/kg WIN 55, 212-2 i.p and 1 mg/kg haloperidol i.p. significantly(P<0.05) decreased exploratory behavior in rats, as evidenced by areduction in the total distance traveled (FIG. 10A), time spentambulating (FIG. 10B), rearing in the open field (FIG. 10C), and zoneentries (FIG. 10D). Herzberg, U., et al., The Analgesic Effects ofR(+)−WIN 55, 212-2 Mesylate, a High Affinity Cannabinoid Agonist, in aRat Model of Neuropathic Pain, Neurosci Lett, 1997, 221:157-60.

1. A compound of structural Formula I

or a salt, ester or prodrug thereof, wherein: R¹ is selected from thegroup consisting of NH₂, NHR⁴, NR⁴R⁵, any carbon atom of which may beoptionally substituted; R² is selected from the group consisting ofhydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, anycarbon atom of which may be optionally substituted; R³ is selected fromthe group consisting of hydrogen, halogen, alkyl, cycloalkyl,heterocycloalkyl, aryl, and heteroaryl, any carbon atom of which may beoptionally substituted; and R⁴ and R⁵ vary independently and areselected from the group consisting of aryl, alkyl, cycloalkyl, aralkyl,alkenyl, and alkynyl, any carbon atom of which may be optionallysubstituted.
 2. A compound of structural Formula II

or a salt, ester or prodrug thereof, wherein: R¹ is selected from thegroup consisting of NH₂, NHR³, NR³R⁴, any carbon atom of which may beoptionally substituted; R² is selected from the group consisting ofhydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, anycarbon atom of which may be optionally substituted; and R³ and R⁴ areindependently selected from the group consisting of aryl, alkyl,cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, and alkynyl, any carbonatom of which may be optionally substituted.
 3. A compound of structuralFormula III

or a salt, ester or prodrug thereof, wherein: R¹ is selected from thegroup consisting of NH₂, NHR⁵, NR⁵R⁶, any carbon atom of which may beoptionally substituted; R² is selected from the group consisting ofhydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, anycarbon atom of which may be optionally substituted; R³ and R⁴ areindependently selected from the group consisting of hydrogen, halogen,alkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl; R⁵ and R⁶ areindependently selected from the group consisting of aryl, alkyl,cycloalkyl, aralkyl, alkenyl, and alkynyl; and when R² is hydrogen, R³is not t-butyl, bromo, methoxy, or


4. A compound of structural Formula IV

or a salt, ester or prodrug thereof, wherein: R¹ is selected from thegroup consisting of NH₂, NHR³, NR³R⁴, any carbon atom of which may beoptionally substituted; R² is selected from the group consisting ofhydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any ofcarbon atom of which may be optionally substituted; R³ and R⁴ areindependently selected from the group consisting of aryl, alkyl,cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, and alkynyl, any carbonatom of which may be optionally substituted; and when R² is hydrogen, R¹is not NH₂,


5. A compound of structural Formula V

or a salt, ester or prodrug thereof, wherein: R¹ is selected from thegroup consisting of cyclohexylamino, piperidinyl, and o-iodoanilino; andR² is optionally substituted phenyl.
 6. A pharmaceutical compositioncomprising a therapeutically-effective amount of a compound, saidcompound selected from a family of compounds of claim 1, 2, 3, 4 or 5,or a pharmaceutically-acceptable salt thereof.
 7. A compound orpharmaceutically acceptable salt thereof as recited in claim 1, or 2,wherein the compound is:


8. A compound or pharmaceutically acceptable salt thereof as recited inclaim 1, or 2, wherein the compound is:


9. A compound or pharmaceutically acceptable salt thereof as recited inclaim 3, 4, or 5, wherein the compound is:


10. A compound of the structural Formula VI:

or a salt, ester or prodrug thereof, wherein: q is an integer rangingfrom 0 to 2 X is absent or present and represents a —O—, —S—, —Se—, NR⁶,SO—, —SO₂—, Z represents a —O—, —S—, —SO—, —SO₂—, —Se— or NR⁷ R¹ isselected from the group consisting of NH₂, NHR⁴, NR⁴R⁵, aryl, aheteroaryl alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbonatom of which may be optionally substituted R² is selected from thegroup consisting of hydrogen, alkyl, cycloalkyl, aralkyl, alkenyl, andalkynyl an alkoxyl, any carbon atom of which may be optionallysubstituted; R³ is selected from the group consisting of aryl, aheteroaryl, alkyl, cycloalkyl, heterocycloalkyl, aralkyl, alkenyl, andalkynyl, any carbon atom of which may be optionally substituted; R⁴ andR⁵ vary independently and are selected from the group consisting ofaryl, alkyl, cycloalkyl, aralkyl, alkenyl, and alkynyl, any carbon atomof which may be optionally substituted, R⁶ is selected from the groupconsisting of hydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, andalkynyl, any carbon atom of which may be optionally substituted, R³ andR⁶ taken together might form a cycloalkyl containing from 3 to 10 carbonatoms and eventually interrupted with one or more hetero atoms or by—CO—, —SO—, —SO₂—, —CHOH— or —NR¹³—; R⁷ is selected from the groupconsisting of hydrogen, aryl, alkyl, cycloalkyl, aralkyl, alkenyl, andalkynyl, any carbon atom of which may be optionally substituted, R⁸ andR⁹ are selected from the group consisting of hydrogen, alkyl, an alkoxylor taken together might form a carbonyl.
 11. A method of modulating acannabinoid receptor comprising contacting the cannabinoid receptor witha heterocyclic compound.
 12. A method of modulating a cannabinoidreceptor comprising contacting the cannabinoid receptor with a compoundrecited in claim
 1. 13. A method of modulating a cannabinoid receptorcomprising contacting the cannabinoid receptor with a compound recitedin claim
 2. 14. A method of modulating a cannabinoid receptor comprisingcontacting the cannabinoid receptor with a compound recited in claim 3.15. A method of modulating a cannabinoid receptor comprising contactingthe cannabinoid receptor with a compound recited in claim
 4. 16. Amethod of modulating a cannabinoid receptor comprising contacting thecannabinoid receptor with a compound recited in claim
 5. 17. A method ofmodulating a cannabinoid receptor comprising contacting the cannabinoidreceptor with a compound recited in claim
 10. 18. A method of treatmentof a cannabinoid receptor-mediated disease comprising administering to asubject in need thereof a therapeutically effective amount of aheterocyclic compound or a pharmaceutically-acceptable salt thereof. 19.A method of treatment of a cannabinoid receptor-mediated diseasecomprising administering to a subject in need thereof a therapeuticallyeffective amount of a compound of claim 1, or apharmaceutically-acceptable salt thereof.
 20. A method of treatment of acannabinoid receptor-mediated disease comprising administering to asubject in need thereof a therapeutically effective amount of a compoundof claim 2, or a pharmaceutically-acceptable salt thereof.
 21. A methodof treatment of a cannabinoid receptor-mediated disease comprisingadministering to a subject in need thereof a therapeutically effectiveamount of a compound of claim 3, or a pharmaceutically-acceptable saltthereof.
 22. A method of treatment of a cannabinoid receptor-mediateddisease comprising administering to a subject in need thereof atherapeutically effective amount of a compound of claim 4, or apharmaceutically-acceptable salt thereof.
 23. A method of treatment of acannabinoid receptor-mediated disease comprising administering to asubject in need thereof a therapeutically effective amount of a compoundof claim 5, or a pharmaceutically-acceptable salt thereof.
 24. A methodof treatment of a cannabinoid receptor-mediated disease comprisingadministering to a subject in need thereof a therapeutically effectiveamount of a compound of claim 10, or a pharmaceutically-acceptable saltthereof.
 25. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of heterocyclic compound, or a pharmaceutically-acceptable saltthereof.
 26. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 1, or a pharmaceutically-acceptable saltthereof.
 27. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 2, or a pharmaceutically-acceptable saltthereof.
 28. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 3, or a pharmaceutically-acceptable saltthereof.
 29. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 4, or a pharmaceutically-acceptable saltthereof.
 30. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 5, or a pharmaceutically-acceptable saltthereof.
 31. A method of treating neuropathic pain in a subject, saidmethod comprising administering to the subject having or susceptible tosaid pain or pain-associated disorder, a therapeutically-effectiveamount of a compound of claim 10, or a pharmaceutically-acceptable saltthereof.
 32. A method of treating addiction in a subject, said methodcomprising administering to the subject having or susceptible to saidpain or pain-associated disorder, a therapeutically-effective amount ofheterocyclic compound, or a pharmaceutically-acceptable salt thereof.33. A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 1, or a pharmaceutically-acceptable salt thereof. 34.A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 2, or a pharmaceutically-acceptable salt thereof. 35.A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 3, or a pharmaceutically-acceptable salt thereof. 36.A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 4, or a pharmaceutically-acceptable salt thereof. 37.A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 5, or a pharmaceutically-acceptable salt thereof. 38.A method of treating addiction in a subject, said method comprisingadministering to the subject having or susceptible to said pain orpain-associated disorder, a therapeutically-effective amount of acompound of claim 10, or a pharmaceutically-acceptable salt thereof.